The value of θ, is limθ→0cos21-cos21-cos2….1-cos21-cos2θsinπθ+4-2θ
24
2
1
limθ→0cos21-cos21-cos2….1-cos21-cos2θsinπθ+4-2θlimθ→0cos21-cos21-cos2….1-cos21-cos2θsinπ(θ+4-2)θ.(θ+4+2)(θ+4+2)limθ→01sinπθ+4+2=1sinπ4=2