hi ive been given this question and im not sure how to do it. 1. a) Prove that cosec^4 x - cot^4 x = cosec^2 x + cot^2 x b) solve for 90 degrees< x < 180 degrees cosec^4 x - cot^4 x = 2 - cot x thanks
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Originally Posted by brooksy hi ive been given this question and im not sure how to do it. 1. a) Prove that cosec^4 x - cot^4 x = cosec^2 x + cot^2 x b) solve for 90 degrees< x < 180 degrees cosec^4 x - cot^4 x = 2 - cot x thanks cosec^4x-cot^4x=(cosec^2x)^2-(cot^2x)^2 =(cosec^2x+cot^2x)(cosec^2x-cot^2x) =(cosec^2x+cot^2x) {a^2-b^2=(a-b)(a+b) and cosec^2x-cot^2x=1}
thanks for that. does anyone know how to do part 2. cheers
Originally Posted by brooksy hi ive been given this question and im not sure how to do it. b) solve for 90 degrees< x < 180 degrees cosec^4 x - cot^4 x = 2 - cot x thanks $\displaystyle cosec^4x-cot^4x=2-cot x$ $\displaystyle cosec^4x-(cosec^4x-1)=2-cot x$ $\displaystyle 1=2-cot x$
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