1) sin5α·cos2α=2) cos6α·cos(-15α)=3) sin3α·sin(-21α)=4) sin+5α)·cos(3-3α)=5)...

Question

1) sin5α·cos2α=
2) cos6α·cos(-15α)=
3) sin3α·sin(-21α)=
4) sin+5α)·cos(3-3α)=
5) cos7α·cos(2+9α)=

1) 2sinαcos3α=
2) 2cos2αcosα=

Answer 1

X^4+X^2-20 или же X^4-6X-27