Sin 6a-cos6a•tg3a ________________ Sin 6a+cos6a•ctg3a

Question

Sin 6a-cos6a•tg3a
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Sin 6a+cos6a•ctg3a

Answer 1

1)sin6a-cos6a*sin3a/cos3a=(sin6a*cos3a-cos6a*sin3a)*cos3a=
=sin(6a-3a)/cos3a=sin3a/cos3a
2)Sin 6a+cos6a•cos3a/sin3a=(sin6a*sin3a+cos6a*cos3a)/sin3a=
=cos(6a-3a)/sin3a=cos3a/sin3a
3)sin3a/cos3a :cos3a/sin3a=sin3a/cos3a *sin3a/cos3a =sin²3a/cos²3a=tg²3a