SOLUTION: help me solve these please approximate the folllowing logarithms to 3 d.p; a)log base 2 23 2)log base3 32 3) 5 to the power2x - 7(5 to the power of x)+10=0

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: help me solve these please approximate the folllowing logarithms to 3 d.p; a)log base 2 23 2)log base3 32 3) 5 to the power2x - 7(5 to the power of x)+10=0      Log On


   

Question 841097: help me solve these please
approximate the folllowing logarithms to 3 d.p;
a)log base 2 23
2)log base3 32
3) 5 to the power2x - 7(5 to the power of x)+10=0
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

Note:log%28a%2C+%28p%29%29+=+log%28b%2Cp%29%2Flog%28b%2C+%28a%29%29+

log%282%2C+%2823%29%29+=+log%2810%2C23%29%2F+log%2810%2C+%282%29%29+

log%283%2C+%2832%29%29+=+log%2810%2C32%29%2F+log%2810%2C+%283%29%29+

3)+5%5E%282x%29-+7%285%5Ex%29+%2B+10+=+0   Let y+=+5%5Ex

  y^2 - 7y + 10 = 0

 (y-5)(y-2) = 0,  y = 5   0r   y = 2

y+=+5%5Ex

 log(5)/log(5) = x

 log(2)/log(5) = x