4. (2023春•淮安区月考)计算求值:(1)sin15∘cos5∘−sin20∘cos15∘cos5∘−cos20∘\frac{\sin 1{5}\circ \cos {5}\circ -\sin 2{0}\circ }{\cos 1{5}\circ \cos {5}\circ -\cos 2{0}\circ }cos15∘cos5∘−cos20∘sin15∘cos5∘−sin20∘;(2)(cos220∘−sin220∘)(1+3tan10∘)(co{s}^{2}2{0}\circ -si{n}^{2}2{0}\circ )(1+\sqrt{3}\tan 1{0}\circ )(cos220∘−sin220∘)(1+3tan10∘).