Simplify Trigonometric Expression

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pbonnie
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Homework Statement


Simplify the following trigonometric expression:
cscθtanθsecθ


Homework Equations


tanθ = sinθ/cosθ
sin^2θ + cos^2θ = 1
cscθ = 1/sinθ
secθ = 1/cosθ
cotθ = 1/tanθ

The Attempt at a Solution


I just want to double check my solution.
cscθtanθsecθ = 1/sinθ x sinθ/cosθ x 1/cosθ
= ((sin^2θ + cos^2θ) x sinθ x 1)/sinθ x cosθ x cosθ
= sin^2θ x 1
= sin^2θ

Thank you!
 
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pbonnie said:

Homework Statement


Simplify the following trigonometric expression:
cscθtanθsecθ


Homework Equations


tanθ = sinθ/cosθ
sin^2θ + cos^2θ = 1
cscθ = 1/sinθ
secθ = 1/cosθ
cotθ = 1/tanθ

The Attempt at a Solution


I just want to double check my solution.
cscθtanθsecθ = 1/sinθ x sinθ/cosθ x 1/cosθ
You're OK to here, but not below. Why not simplify by doing some cancelling?
pbonnie said:
= ((sin^2θ + cos^2θ) x sinθ x 1)/sinθ x cosθ x cosθ
= sin^2θ x 1
= sin^2θ

Thank you!
 
pbonnie said:
cscθtanθsecθ = 1/sinθ x sinθ/cosθ x 1/cosθ
= ((sin^2θ + cos^2θ) x sinθ x 1)/sinθ x cosθ x cosθ

What you have above isn't incorrect, but it isn't helpful, either. I don't know how you got the line that follows (sin^2θ x 1) from this.
 
Hmm okay would I cancel out the sinθ in 1/sinθ x sinθ/cosθ x 1/cosθ so it simplifies to 1/cos^2θ?