ω2Rcosθ\omega^{2} \mathrm{R} \cos \thetaω2Rcosθ
ω2R\omega^{2} \mathbf{R}ω2R
ω2Rcos2θ\omega^{2} R \cos ^{2} \thetaω2Rcos2θ
ωRcosθ\omega R \cos \thetaωRcosθ