①sin(α+180°)cos(-α)sin(-α-180°)和②sin³(-α)cos(2π+α)tan(-α-π)化简
问题描述:
①sin(α+180°)cos(-α)sin(-α-180°)和②sin³(-α)cos(2π+α)tan(-α-π)化简
答
①sin(α+180°)cos(-α)sin(-α-180°)
=-sin(α+180°)cosαsin(α+180°)
=-sinαcosαsinα
=-sin²αcosα
sin³(-α)cos(2π+α)tan(-α-π)
=sin³αcosαtan(α+π)
=sin³αcosαtanα
=sin³αsinα
=sin^4α