化简cos2(-α)-tan(2π+α)/sin(-α)
问题描述:
化简cos2(-α)-tan(2π+α)/sin(-α)
答
=cos2a+tana/sina=cos2a+1/cosa=(cosacosa-sinasina+cosacosa+sinasina)/cosa=2cosa
化简cos2(-α)-tan(2π+α)/sin(-α)
=cos2a+tana/sina=cos2a+1/cosa=(cosacosa-sinasina+cosacosa+sinasina)/cosa=2cosa