We are asked to solve two separate problems. (a) Solve the equation $8^{-x^2+x} = 2^{5x-1}$ for $x$. (b) Solve the equation $\log_a(2p+1) + \log_a(3p-10) = \log_a(11p)$ for $p$, given that $p>0$.

AlgebraExponentsLogarithmsQuadratic EquationsEquation SolvingLogarithm PropertiesFactorization
2025/6/4

1. Problem Description

We are asked to solve two separate problems.
(a) Solve the equation 8x2+x=25x18^{-x^2+x} = 2^{5x-1} for xx.
(b) Solve the equation loga(2p+1)+loga(3p10)=loga(11p)\log_a(2p+1) + \log_a(3p-10) = \log_a(11p) for pp, given that p>0p>0.

2. Solution Steps

(a) Solve 8x2+x=25x18^{-x^2+x} = 2^{5x-1}.
We can rewrite 88 as 232^3, so the equation becomes (23)x2+x=25x1(2^3)^{-x^2+x} = 2^{5x-1}.
This simplifies to 23(x2+x)=25x12^{3(-x^2+x)} = 2^{5x-1}.
Since the bases are equal, we can equate the exponents:
3(x2+x)=5x13(-x^2+x) = 5x-1
3x2+3x=5x1-3x^2+3x = 5x-1
0=3x2+2x10 = 3x^2+2x-1
Now, we can solve this quadratic equation for xx. We can factor the quadratic:
3x2+2x1=(3x1)(x+1)=03x^2+2x-1 = (3x-1)(x+1) = 0
So, 3x1=03x-1=0 or x+1=0x+1=0.
This gives us x=13x = \frac{1}{3} or x=1x = -1.
(b) Solve loga(2p+1)+loga(3p10)=loga(11p)\log_a(2p+1) + \log_a(3p-10) = \log_a(11p).
Using the logarithm property loga(x)+loga(y)=loga(xy)\log_a(x) + \log_a(y) = \log_a(xy), we have:
loga((2p+1)(3p10))=loga(11p)\log_a((2p+1)(3p-10)) = \log_a(11p)
Since the bases of the logarithms are equal, we can equate the arguments:
(2p+1)(3p10)=11p(2p+1)(3p-10) = 11p
6p220p+3p10=11p6p^2 - 20p + 3p - 10 = 11p
6p217p10=11p6p^2 - 17p - 10 = 11p
6p228p10=06p^2 - 28p - 10 = 0
Divide by 2:
3p214p5=03p^2 - 14p - 5 = 0
Now, we can solve this quadratic equation for pp. We can factor the quadratic:
3p214p5=(3p+1)(p5)=03p^2 - 14p - 5 = (3p+1)(p-5) = 0
So, 3p+1=03p+1=0 or p5=0p-5=0.
This gives us p=13p = -\frac{1}{3} or p=5p = 5.
Since we are given that p>0p>0, we must discard the negative solution p=13p = -\frac{1}{3}.
Also, we need to check if 2p+1>02p+1>0 and 3p10>03p-10>0 for the logarithmic terms to be defined. If p=5p=5, we have 2p+1=2(5)+1=11>02p+1 = 2(5)+1 = 11 > 0 and 3p10=3(5)10=1510=5>03p-10 = 3(5)-10 = 15-10 = 5 > 0. So p=5p=5 is a valid solution.

3. Final Answer

(a) x=13,1x = \frac{1}{3}, -1
(b) p=5p = 5

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