Первый помогите пожалуйста

((m-4)/(m+4) - (m+4)/(m-4)) . (m²-16)/16 =
=( (m-4)²-(m+4)²)/(m²-16) ) . (m²-16)/16=
=(m²-8m+16-m²-8m-16)/16=(-16m)/16=-m
(
m≠-4,m≠4)
Otvet: -m

(cos²α-sin²α)/(cosα-sinα) -tgαcosα=(cosα+sinα)(cosα-sinα)/(cosα-sinα)-tgαcosα=
´=(cosα+sinα)-sinαcosα/cosα=cosα+sinα-sinα=cosα

((cosα+sinα)²-1)/(ctgα-sinαcosα)=(cos²α+2cosαsinα+sin²α-1)/(cosα/sinα -sinαcosα)=
=(1+2cosαsinα-1)/(cosα-sin²αcosα)/sinα=
=2cosαsinαsinα/(cosα-sin²αcosα)=2cosαsin²α/cosα(1-sin²α)=
=2sin²α/(1-sin²α)=2sin²α/cos²α=2tg²α