√128*Cos^2*3Π/8-√32=√32(2cos^2*3Π/8-1)=√32(cos2 3Π/8)= √32cos 3Π/4=√32*√2/2=√16=4

Question

√128*Cos^2*3Π/8-√32=√32(2cos^2*3Π/8-1)=√32(cos2 3Π/8)= √32cos 3Π/4=√32*√2/2=√16=4

Answer 1

= √32*4 * cos^2 3π8- √32= √32*√4*cos^2 3π/8-√32=√32(2* cos^2 3π8- 1)=√32cos(90+45)=√32(-sin45)=√31/1 * -√2/2= -√32*√2/1*2=√64/2= -8/2=-4