Question

2) sin^b - 1;
3) sin^2f+ cos^2f + 1;​

Answer 1

$\boxed {sin^2\beta +cos^2\beta =1}\\\\\\2)\; \; sin^2\beta -1=cos^2\beta \\\\\\3)\; \; \underbrace{sin^2\varphi +cos^2\varphi }_{1}+1=1=1=2$