Question

сократите дробь (2^n+2^-n)/(4^n+1)

Answer 1

$frac{2^{n}+2^{-n}}{4^{n}+1 }=frac{2^{n}+frac{1}{2^{n}}}{4^{n}+1 } =frac{(2^{n})^{2}+1}{2^{n}(4^{n}+1)}=frac{4^{n}+1 }{2^{n}(4^{n}+1)}=frac{1}{2^{n} }$