= (sin(540°+60°)+ tg(450+30))cos(360-30)=(-sin60-ctg30)cos30=-1,5
3(4x-y)^2-2(x-y)(x+y)+4(x+3y)^2
3(16x^2-8xy+y^2)-2(x^2-y^2)+4(x^2+6xy+9у^2)
48х^2-24ху+3у^2-2х^2+2у^2+4х^2+24ху+36у^2
50х^2+41у^2
Если х=-1/5; у=-1, то 50(-1/5)^2+41•(-1)^2
50•0,04+41=2+41=43
5*(1/5)^2 - 16*1/5= 5/25-16/5= 1/5-16/5 = -15/5 = -3