已知sina+cosa=p,求(1)sina*cosa(2)sin^2a-cos^2a(3)sin^3a+-cos^3a(4)sin^4a+-ctg^3a
问题描述:
已知sina+cosa=p,求(1)sina*cosa(2)sin^2a-cos^2a(3)sin^3a+-cos^3a(4)sin^4a+-ctg^3a
答
1,(p^2-1)/2
2,p*根号(2-p^2)