Question

5^х+1+5^х+5^х-1=155 помогите решить !)))

Answer 1

5^х+1+5^х+5^х-1=155 
15^x=155
$x^{2}$=$frac{155}{15}$
x=$sqrt{ frac{155}{15} }$

Answer 2

$5^{x+1} + 5^{x} + 5^{x-1} = 155 \ 5^{x}*5^{1}+5^{x} +5^{x} :5^{1} = 155 \ 5^{x}* (1*5+1+1:5) = 155 \ 5^{x}* frac{31}{5} = 155 \ 5^{x} = 155 * frac{5}{31} \ 5^{x} = 25 \ 5^{x} = 5^{2} \ x = 2$
Вот так.