How do you simplify f(theta)=-2csc(theta/4)-cot(theta/2)+2sin(theta/4)f(θ)=2csc(θ4)cot(θ2)+2sin(θ4) to trigonometric functions of a unit thetaθ?

1 Answer
Jul 23, 2016

=(-2(1+sqrt(1/2(1+costheta))))/sqrt(1/2(1-sqrt(1/2(1+costheta))))-(1+costheta)/sintheta=2(1+12(1+cosθ))12(112(1+cosθ))1+cosθsinθ

Explanation:

f(theta)=-2csc(theta/4)-cot(theta/2)+2sin(theta/4)f(θ)=2csc(θ4)cot(θ2)+2sin(θ4)

=2sin(theta/4)-2/sin(theta/4)-cot(theta/2)=2sin(θ4)2sin(θ4)cot(θ2)

=(2sin^2(theta/4)-2)/sin(theta/4)-(2cos^2(theta/2))/(2sin(theta/2)cos(theta/2))=2sin2(θ4)2sin(θ4)2cos2(θ2)2sin(θ2)cos(θ2)

=(-2(1-sin^2(theta/4)))/sin(theta/4)-(1+costheta)/sintheta=2(1sin2(θ4))sin(θ4)1+cosθsinθ

=(-2cos^2(theta/4))/sin(theta/4)-(1+costheta)/sintheta=2cos2(θ4)sin(θ4)1+cosθsinθ

=(-2(1+cos(theta/2)))/sqrt(1/2(1-cos(theta/2)))-(1+costheta)/sintheta=2(1+cos(θ2))12(1cos(θ2))1+cosθsinθ

=(-2(1+sqrt(1/2(1+costheta))))/sqrt(1/2(1-cos(theta/2)))-(1+costheta)/sintheta=2(1+12(1+cosθ))12(1cos(θ2))1+cosθsinθ

=(-2(1+sqrt(1/2(1+costheta))))/sqrt(1/2(1-sqrt(1/2(1+costheta))))-(1+costheta)/sintheta=2(1+12(1+cosθ))12(112(1+cosθ))1+cosθsinθ