SOLUTION: can you help me to solve this problem please? {{{(2x-1)^(2/3)=16}}}

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Question 482539: can you help me to solve this problem please?
%282x-1%29%5E%282%2F3%29=16

Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
%282x-1%29%5E%282%2F3%29=16
take the cube of both sides of the equation
%282x-1%29%5E%282%2A3%2F3%29=16%5E3
%282x-1%29%5E2=16%5E3
4x^2-4x+1=4096
4x^2-4x-4095=0
Find the roots of the equation by quadratic formula

a= 4 ,b= -4 ,c= -4095

b^2-4ac= 16 + 65520
b^2-4ac= 65536
x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=%28-12%2B21%29%2F%2812%29
x1=( 4 + 256 )/ 8
x1= 32.5
x2=( 4 -256 ) / 8
x2= -31.5
The roots are 32.5 & -31.5
32.5 satisfies the equation
CHECK
((2*32.5)-1)^(2/3)=16
m.ananth@hotmail.com