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How would I prove this is 4 or more steps.

csc^2 Θ – cot^2 Θ = cot^2 Θ (1-cos^2 Θ)
sec^2 Θ


(csc -cot is all being divided by sec) (and you cant mess with the right side)

2007-10-23 15:27:39 · 2 answers · asked by Anonymous in Science & Mathematics Mathematics

2 answers

(cosec^2 Θ - cot^2 Θ) / (sec^2 Θ)
= (1/sin^2 Θ - cos^2 Θ / sin^2 Θ) / (1/cos^2 Θ)
= (cos^2 Θ / sin^2 Θ) (1 - cos^2 Θ)
= cot^2 Θ (1 - cos^2 Θ)

Of course, since 1 - cos^2 Θ = sin^2 Θ we can simplify this to cot^2 Θ sin^2 Θ = cos^2 Θ.

2007-10-23 15:32:53 · answer #1 · answered by Scarlet Manuka 7 · 0 0

Split the left into 2 fractions and make replacements:

(1/sin^2 Θ) / (1/cos^2 Θ) - (cos^2 Θ/sin^2 Θ)/(1/cos^2 Θ)

flip and multiply to get

cos^2 Θ / sin^2 Θ - cos^4 Θ/ sin^2 Θ
= [cos^2 Θ - cos^4 Θ]/sin^2 Θ

Factor out a cos^2 Θ

cos^2 Θ (1 - cos^2 Θ) over sin^2 Θ
Replace cos^2 Θ / sin^2 Θ with cot^2 Θ and you have it

2007-10-23 22:37:02 · answer #2 · answered by hayharbr 7 · 1 0

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