Question

15^cosx=3^cosx * (0.2)^-sinx
Помогите

Answer 1

$3^{cosx}* 5^{cosx} = 3^{cosx}* 5^{sinx}$
$5^{cosx}= 5^{sinx}$
$cosx=sinx$
$cosx-sinx=0 :cosx$
$1-tgx=0$
$tgx=1$
$x= frac{ pi }{4}+ pi n, neZ$