cos x + √2 = -Sin (x/2 - x) untuk 0

pi/2=90
sin(90-x)=cos(x)

cos(x)+akar(2)= - cos(x)
cos(x) + cos(x) = akar(2)
2 cos(x) = akar(2)
cos (x) = 1/2 akar(2) = cos (45) = cos (360-45)
jadi x=45 atau x=360-45=....