化简cos(1-π)+cos(3π+1)=
问题描述:
化简cos(1-π)+cos(3π+1)=
答
cos(1-π)+cos(3π+1)=cos(π-1)+cos(π+1)=-cos1-cos1=-2cos1
化简cos(1-π)+cos(3π+1)=
cos(1-π)+cos(3π+1)=cos(π-1)+cos(π+1)=-cos1-cos1=-2cos1