Question

Solve

Answer 1

$f(x)=15\cdot0.2^x\\ 0.2^x=\dfrac{f(x)}{15}\\ x=\log_{0.2}\dfrac{f(x)}{15}\\\\\\ f(x)=40+1^x\\ 1^x=f(x)-40\\ x=\log_1(f(x)-40)$