:а)3^2x-1-3^2x+3^2x+3=237 b)5^2x-30*5^x+125=0 c) (1/36)^-10 корень x=2^5x*3^5x

3^( 2x - 1 ) - 3^2x + 3^( 2x + 3 ) = 237 
3^2x * ( ( 1/3 ) - 1 + 27 ) = 237 
3^2x = 237 : 26 1/3 
3^2x = 237 : 79/3 
3^2x = 9 
3^2x = 3^2 
2x = 2 
x = 1 

5^( 2x - 30 ) - 30*5^( x + 125 ) = 0 
5^( 2x - 30 ) = 30*5^( x + 125 ) 
5 ^ ( 2x - 30 ) : 5 ^ ( x + 125 ) = 30 
5 ^ ( 2x - 30 - x - 125 ) = 30 
5 ^ ( x - 155 ) = 30 
x - 155 = log₅ 30 
x = ( log ₅ 30 ) + 155 

( 1/36 ) ^ - 10√x = 2^5x * 3^ 5x 
( 6 ^ - 2 ) ^ - 10√x = 6 ^ 5x 
6 ^ 20√x = 6 ^ 5x 
20√x = 5x 
√x = a 
20a = 5a^2 
20a - 5a^2 = 0 
5a( 4 - a ) = 0 
5a = 0 ==> a = 0 
4 - a = 0 ==> a = 4 
√ x = 0 ==> x = 0 
√ x = 4 ; x = 16