Question

Can I please get help with these problems?.

Answer 1

for the first one you can replace \(\sin^2(x)\) by \(1-\cos^2(x)\) to get \[\cos(x)-(1-\cos^2(x))-1\]

Answer 2

that will get you
\[\cos^2(x)+\cos(x)-2\]which factors

Answer 3

the second one is easier, since \(z^2-b^2=(a+b)(a-b)\) you have
\[\cot^2(x)-1=(\cot(x)+1)(\cot(x)-1)\]