Question

Тригонометрическая задача​

Answer 1

перепишем условие так

(сos(π/2-6α)-sin4α-sinα)/(sin(π/2+6α)+cos4α-cosα)=

((sin6α-sin4α)-sinα)/((cos6α+cos4α)-cosα)=

(2sinα*cos5α-sinα)/(2cos5α*cosα-cosα)=sinα*(2cos5α-1)/(cosα*(2cos5α-1))

=sinα/cosα=tgα