How do you find the exact value of sin60cos30 + sin30cos60?

##30^o and 60^o are angles of one of the standard triangles##
##sin(30^o) = 1/2##
##cos(30^o) = sqrt(3)/2##
##sin(60^o) = sqrt(3)/2##
##cos(60^o) = 1/2##
So
##sin(60^o)*cos(30^o) + sin(30^o)*cos(60^o)##
##=(sqrt3/2)(sqrt3/2) +(1/2)(1/2) = 3/4 +1/4##
##=1##