Solving the equation
I'm working on this algebraic expression: starting with \(3x + 1 + x - 1 - 2\sqrt{(3x + 1)(x - 1)} = 4\). After some rearrangement, I find that \( \sqrt{(3x + 1)(x - 1)} = 2(x - 1)\). To ensure non-negative solutions, I need \(x\) to be at least 1. Squaring both sides leads to the equation \( (3x + 1)(x - 1) = 4(x - 1)^2\), which expands and simplifies to find the roots at 1 and 5.Inspecting exponential equation
I'm trying to solve \(81 = -810\), which doesn't seem right. Maybe the original equation should involve substitutions with exponents to form a quadratic or cubic. For instance, reworking \(27^{x-\frac{2}{3}} - \frac{2}{81}\cdot 9^{x+2} = 9\) might involve transforming the base to \(3^x\). I'll also check the potential roots for a cubic equation and consider if any transcription errors occurred. It's complex, but I'll keep refining my approach!Exploring exponent substitutions
I'm considering if the first exponent could be \(x-\frac{2}{3}\), which might allow me to transform the equation into a form involving \(3^{x-\?}\) and align the second part to a square. I’ll derive different substitutions, letting \(a = 27^{x-?}\), and think about how to express both exponents in terms of \(3^{?}\). The first one appears as \(3^{3x-2}\) and the second as \(3^{2x+4}\). However, the difference seems to be \(x-6\), which looks off. I need to dig deeper!Analyzing the equation
I'm looking at the equation where \(3^{x?}\) suggests a cubic or quadratic form with non-integer coefficients. Substituting \(y=3^{x?}\) doesn't seem simple. Perhaps \(x-\frac{2}{3}\) is part of it, and the equation involves bases like \(27^{x-\frac{2}{3}}\) and \(9^{x+2}\). After some manipulations with coefficients and simplifications, I'm questioning the rationality of potential roots. There might be a known root I need to investigate numerically, possibly something near \(x \approx 2.64\). I'll visually examine the equation for clarity.Evaluating the equation and image
I'm wondering if there's a dot or multiplication involved in the term \(9^{x+2}\). It seems like equation number 14 might not be properly numbered due to the image, suggesting another problem might be hidden there. The user has asked about the assignment related to this image, which is mostly clear. I don't want to ask for clarification unless it's absolutely necessary. I think I’ll aim to solve this numerically or maybe see if there's a nice answer. I'll examine the image closely!Factoring cubic equations
I’m calculating for a depressed cubic where p = -108 and q = -513. I need to find the discriminant and see if I made any mistakes in my calculations. The values I obtained lead to factoring 76545, which seems complicated but doable. I’m checking the factorization step by step, mapping out roots and looking for real roots. I’m also considering if there’s a trigonometric alternative since there seems to be just one real root. Let’s explore these approaches further.Examining potential expressions
I think I misread the first exponent as \(x - \frac{2}{3}\), but maybe it’s the fraction attached to the base. The expression might actually be \(27^{x - \frac{2}{3}} - \frac{2}{81} \cdot 9^{x+2} = 9\). They could expect a substitution like \(3^x = t\) for a cubic approach, rather than a simple exponential. I’ll need to break down prior equations to analyze their structure; it's possibly more complex than it seems.Analyzing exponent structure
I’m thinking about the possibility that the exponent is actually \(\frac{x-2}{3}\), where it would show up with "x - 2" over 3. From the screenshot, it seems like I might see \(27^{x - \frac{2}{3}}\) when it could actually be \(27^{\frac{x-2}{3}}\). This is important! If it indeed is \((x-2)/3\), the fraction bar would cover “x - 2” fully. I need to parse the text carefully to clarify what's really being presented.Exploring cubic equations
I wonder if this problem can be tackled using a simple inequality, though there may not be an exact expectation. I'm considering the derivative for the function f(t) = t³ - 18t² - 81, which gives f'(t) = 3t(t-12). It’s decreasing on (0,12) and increasing after that. Evaluating at f(0) shows -81, and at f(12) seems to lead to -945. So, it looks like there's a positive root around 18.24, with a possible approximation of x 2.64. I’m curious if the question suggests "solve" and accepts numerical methods.Structuring algebra problems
I'm working through the equations \(x^2 - 9x + 32 = 6\sqrt{x^2 - 9x + 24}\) and \(x^2 - 11x + 22 = 4\sqrt{x^2 - 11x + 19}\).
I want to solve them systematically. First, I should provide a brief answer followed by key steps or reasoning and verify if needed. I need to create an answers list and clarify my methods. I might consider whether I need to include the final step for equation #14.Refining cubic roots
I’m working through a cubic equation where I calculated some values: a³ and ln values to a total. I’m estimating that my x is around 2.643 — but I wonder if there’s a simpler, exact root by changing my approach. Maybe a transformation would help. I need to check the original equation interpretation, as it seems I might have missed something related to an exponent or substitution, possibly involving \(y=3^{x-2}\). I’ll keep exploring this!Transforming equations
I'm trying to express my equation with \(y=3^{x-2}\). First, I set up \(3^{3x-2}\) and relate it to \(y\), which leads to \(x= \log_3 y + 2\). I notice I have an exponent and convert it to \(81y^3\).
Then I look at the next part, \(2 \cdot 3^{2x}\), which simplifies down to \(162y^2\). This gives me a cubic equation: \(9y^3 - 18y^2 = 1\). I think I need to explore potential roots for \(y\) from here.Verifying equations and extraneous roots
I’m going through and checking the substitution results for exponential equations, making sure I’ve accounted for all domains and extraneous roots. For example, I see there are results like x=3, x=1.5, and others. I wonder about equation 4 with the radical and if x=1/3 is extraneous, due to the negative RHS. After verifying, it looks like I can discard it. Overall, I’m just making sure my calculations hold up!Solving an equation
I’m looking at the equation where \(t = 3^x > 0\). I notice that \(27^{x-2/3}\) can be rewritten as \(3^{3x-2}\), giving me \(t^3/9\). Then, I have \(\frac{2}{81}9^{x+2}\), which simplifies down to \(2t²\). I end up with the equation \(t^3/9 - 2t² = 9\), and this leads to \(t³ - 18t² - 81 = 0\). I need to find the positive root \(t_0 \approx 18.2434\) and determine if it's unique.Evaluating task expectations
I'm considering that if the school task doesn’t expect a numerical answer, providing an exact radical expression could be ideal. I’ll include that expression in parentheses to make it clear. It seems important to clarify whether they want a more precise mathematical representation rather than a simplified number. I just want to make sure I'm meeting the assignment's requirements correctly!Considering exponent readings
I'm thinking about the exponent in the equation \(x - \frac{2}{3}\), and wondering if there might be alternative interpretations for the exponents in equations 6, 8, and 14. For instance, in equation 6, I see the expression \(4^x - 3 \cdot 2^{x+1} + 8 = 0\). It's interesting to explore different ways exponents can be analyzed in these equations! Let’s investigate further.Evaluating polynomial equations
I’m running through some polynomial equations and considering various calculations involving exponents and roots. I’m checking if certain substitutions work out, but it seems like they may not yield simple integer roots, which could be tricky for someone at a school level. I think I might want to clarify if the user expects the full set of solutions since the polynomial may not be designed to solve neatly. Also, I wonder if the image is clear enough for them to review.Clarifying superscripts and equations
I need to be careful because misreading a small superscript could lead to an incorrect answer for equation #14. It’s important to explicitly mention reading the equation correctly. I might even add a note suggesting that if there’s a different exponent, the user should share a clearer fragment. However, I want to make sure my final answer directly assists them. I'm also considering if the equation might include \(\frac{x-2}{3}\) or if it truly is \(x - \frac{2}{3}\). I should clarify these aspects to avoid confusion.Calculating a numeric solution
I’m working through an equation where \(t_0\) is the unique positive root of a cubic function. This involves expressing \(t_0\) with a radical expression for rigor. I calculate \(t_0\) as \(6+\sqrt[3]{\frac{513+27\sqrt{105}}{2}}+\sqrt[3]{\frac{513-27\sqrt{105}}{2}}\) and approximate it to be around 18.24. I’ll now compute the logarithmic value \(x=\log_3 t_0\) more accurately, fine-tuning my calculations to ensure precision as I refine my values for \(x\).Calculating values and derivatives
I'm working on some calculations related to logarithms and cubic roots. I’ve computed several values and checked them against one another. For instance, I found the natural log of 18 while exploring potential relations. I also addressed how to interpret an equation. There’s quite a bit of detail involved, with values shifting subtly through each calculation. It seems like I’m getting closer to the approximate values I need, but I’ll verify them to ensure accuracy.Clarifying verification steps
It seems the user wants to verify results, so I should include a line with my equations:
- \( \sqrt{9} + \sqrt{4} = 5 \)
- \( \sqrt{4} - 0 = 2 \)
- \( \sqrt{9} + \sqrt{4} = 5 \)
- \( \sqrt{9} = 3 \)
For number 2, I need to ensure I check for multiple roots. The answer list should focus on clarity with specific solutions like \(x=3\) and others. I noticed inconsistencies earlier in my polynomial derivation that need to be corrected. It’s important to keep everything concise and clear!Verifying the equation
I’m looking at the equation \(100x + 100 = x² - 46x + 529\). Reorganizing it gives me \(0 = x² - 146x + 429\). That seems accurate!
I want to be confident that each step is clear and correct since it’s essential to convey this properly. Now I’ll focus on solving the quadratic equation. I need to ensure my arithmetic is spot on, so I double-check my calculations to prevent any mistakes. Let’s keep going with this!
Краткие ответы
- \(x=3\)
- \(x=1;\ 5\)
- \(x=2\)
- \(x=2\)
- \(x=1\)
- \(x=1;\ 2\)
- \(x=2\)
- \(x=2\)
- \(x=-1;\ 3\)
- \(x=-2;\ 1\)
- \(x=-1;\ 0;\ 7;\ 8\)
- \(x=1;\ 4;\ 5;\ 8\)
- \(x=1;\ 2;\ 9;\ 10\)
- \(x\approx2{,}643\) — разбор последнего уравнения приведён ниже.
1–5. Иррациональные уравнения
При возведении в квадрат обязательно учитываем ОДЗ и неотрицательность правой части.
1)
\[ \sqrt{2x+3}+\sqrt{x+1}=5 \]
\[ \sqrt{2x+3}=5-\sqrt{x+1} \]
После возведения в квадрат:
\[ 2x+3=26+x-10\sqrt{x+1} \]
\[ 10\sqrt{x+1}=23-x \]
Ещё раз возводим в квадрат:
\[ 100(x+1)=(23-x)^2 \]
\[ x^2-146x+429=0 \]
\[ x=3\quad\text{или}\quad x=143. \]
Но \(23-x\ge0\), поэтому \(x\le23\). Подходит только
\[ \boxed{x=3}. \]
Проверка:
\[ \sqrt9+\sqrt4=3+2=5. \]
2)
\[ \sqrt{3x+1}-\sqrt{x-1}=2 \]
\[ \sqrt{3x+1}=2+\sqrt{x-1} \]
Возводим в квадрат:
\[ 3x+1=4+4\sqrt{x-1}+x-1 \]
\[ x-1=2\sqrt{x-1} \]
Пусть \(t=\sqrt{x-1}\), тогда:
\[ t^2=2t \]
\[ t(t-2)=0 \]
\[ t=0\quad\text{или}\quad t=2. \]
Следовательно,
\[ \boxed{x=1;\ 5}. \]
3)
\[ \sqrt{5x-1}+\sqrt{x+2}=5 \]
\[ \sqrt{5x-1}=5-\sqrt{x+2} \]
После возведения в квадрат:
\[ 5x-1=x+27-10\sqrt{x+2} \]
\[ 10\sqrt{x+2}=28-4x \]
Возводим в квадрат:
\[ 100(x+2)=(28-4x)^2 \]
\[ 4x^2-81x+146=0 \]
\[ x=2\quad\text{или}\quad x=\frac{73}{4}. \]
Условие \(28-4x\ge0\) даёт \(x\le7\), поэтому
\[ \boxed{x=2}. \]
4)
\[ \sqrt{x^2+3x-1}=2x-1 \]
Правая часть должна быть неотрицательной:
\[ 2x-1\ge0. \]
Возводим в квадрат:
\[ x^2+3x-1=(2x-1)^2 \]
\[ 3x^2-7x+2=0 \]
\[ x=2\quad\text{или}\quad x=\frac13. \]
Число \(\frac13\) не подходит, так как \(2x-1<0\). Поэтому
\[ \boxed{x=2}. \]
5)
\[ \sqrt{x^2+2x+6}=2x+1 \]
\[ 2x+1\ge0. \]
Возводим в квадрат:
\[ x^2+2x+6=(2x+1)^2 \]
\[ 3x^2+2x-5=0 \]
\[ x=1\quad\text{или}\quad x=-\frac53. \]
Корень \(-\frac53\) не подходит, поскольку правая часть отрицательна. Значит,
\[ \boxed{x=1}. \]
6–10. Показательные уравнения
6)
\[ 4^x-3\cdot2^{x+1}+8=0 \]
Пусть \(t=2^x>0\). Тогда \(4^x=t^2\), \(2^{x+1}=2t\):
\[ t^2-6t+8=0 \]
\[ (t-2)(t-4)=0. \]
\[ 2^x=2\Rightarrow x=1, \qquad 2^x=4\Rightarrow x=2. \]
\[ \boxed{x=1;\ 2}. \]
7)
\[ 3^{2x}-4\cdot3^x-45=0 \]
Пусть \(t=3^x>0\):
\[ t^2-4t-45=0 \]
\[ (t-9)(t+5)=0. \]
Так как \(t>0\), \(t=9\):
\[ 3^x=9=3^2. \]
\[ \boxed{x=2}. \]
8)
\[ 5^{x+1}-5^{x-1}=120 \]
Выносим \(5^{x-1}\):
\[ 5^{x-1}(25-1)=120 \]
\[ 24\cdot5^{x-1}=120 \]
\[ 5^{x-1}=5 \]
\[ \boxed{x=2}. \]
9)
\[ 2^{x^2-2x}=8=2^3 \]
Приравниваем показатели:
\[ x^2-2x=3 \]
\[ x^2-2x-3=0 \]
\[ (x-3)(x+1)=0. \]
\[ \boxed{x=-1;\ 3}. \]
10)
\[ 3^{x^2+x}=9=3^2 \]
\[ x^2+x=2 \]
\[ x^2+x-2=0 \]
\[ (x+2)(x-1)=0. \]
\[ \boxed{x=-2;\ 1}. \]
11–13. Замена переменной
11)
\[ x^2-7x+4=4\sqrt{x^2-7x+1} \]
Пусть
\[ y=x^2-7x+1,\qquad y\ge0. \]
Тогда \(x^2-7x+4=y+3\):
\[ y+3=4\sqrt y. \]
Пусть \(t=\sqrt y\), \(t\ge0\):
\[ t^2+3=4t \]
\[ t^2-4t+3=0 \]
\[ t=1\quad\text{или}\quad t=3. \]
Значит, \(y=1\) или \(y=9\).
- При \(y=1\):
\[ x^2-7x+1=1 \]
\[ x(x-7)=0 \]
\[ x=0;\ 7. \]
- При \(y=9\):
\[ x^2-7x+1=9 \]
\[ x^2-7x-8=0 \]
\[ x=-1;\ 8. \]
Ответ:
\[ \boxed{x=-1;\ 0;\ 7;\ 8}. \]
12)
\[ x^2-9x+32=6\sqrt{x^2-9x+24} \]
Пусть
\[ y=x^2-9x+24. \]
Тогда:
\[ y+8=6\sqrt y. \]
Пусть \(t=\sqrt y\):
\[ t^2+8=6t \]
\[ t^2-6t+8=0 \]
\[ t=2;\ 4. \]
Следовательно, \(y=4\) или \(y=16\).
При \(y=4\):
\[ x^2-9x+24=4 \]
\[ x^2-9x+20=0 \]
\[ x=4;\ 5. \]
При \(y=16\):
\[ x^2-9x+24=16 \]
\[ x^2-9x+8=0 \]
\[ x=1;\ 8. \]
\[ \boxed{x=1;\ 4;\ 5;\ 8}. \]
13)
\[ x^2-11x+22=4\sqrt{x^2-11x+19} \]
Пусть
\[ y=x^2-11x+19. \]
Тогда:
\[ y+3=4\sqrt y. \]
Пусть \(t=\sqrt y\):
\[ t^2-4t+3=0 \]
\[ t=1;\ 3. \]
Значит, \(y=1\) или \(y=9\).
При \(y=1\):
\[ x^2-11x+18=0 \]
\[ x=2;\ 9. \]
При \(y=9\):
\[ x^2-11x+10=0 \]
\[ x=1;\ 10. \]
\[ \boxed{x=1;\ 2;\ 9;\ 10}. \]
14. Последнее уравнение
На фото последняя строка читается так:
\[ 27^{x-\frac23}-\frac{2}{81}\cdot9^{x+2}=9. \]
Пусть \(t=3^x>0\). Тогда:
\[ 27^{x-\frac23}=3^{3x-2}=\frac{t^3}{9}, \]
\[ \frac{2}{81}\cdot9^{x+2} =\frac{2}{81}\cdot3^{2x+4} =2t^2. \]
Получаем:
\[ \frac{t^3}{9}-2t^2=9. \]
Умножим на \(9\):
\[ t^3-18t^2-81=0. \]
У этого уравнения единственный положительный корень:
\[ t\approx18{,}2434. \]
Поэтому:
\[ x=\log_3 18{,}2434\approx2{,}643. \]
Итак,
\[ \boxed{x\approx2{,}643}. \]
В первых пяти уравнениях лишние корни отброшены по ОДЗ и знаку правой части; остальные найденные корни подстановкой удовлетворяют исходным уравнениям.