1)sin22,5+sin²75=√(1-cos45)/2+(1-cos150)/2
√(2-√2)/2+(1+sin30°)/2=1/2√(2-√2)+3/4
2)2cos²4x-1=0
cos8x=0
8x=π/2+πk
x=π/16+πk/8
√(2-√2)/2+(1+sin30°)/2=1/2√(2-√2)+3/4
2)2cos²4x-1=0
cos8x=0
8x=π/2+πk
x=π/16+πk/8