If you can. i will give brainiest to best answer. this question is a calculus/trigonometry question. i ask that you look over my work, but if you don't have the time, i ask that you me answer the questions i don't know.

7 is incorrect. The answer should be -4. Here's how I'd derive it:

With , we should expect . If , then

Also,

so we should expect and

You seem to be taking

but this is not an identity.

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8 is incorrect. Just a silly mistake, you swapped the order of the terms in the numerator. It should be

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9. Use the identity from (7). lies in the second quadrant, so

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12.

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13.

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14.

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15.

false

step-by-step explanation:

false.   two legs of the trapezoid would be congruent, but the other two would not.   were all the legs congruent, then we'd have a square; were the 2 shorter sides congruent and the 2 longer sides also congruent, we'd have a rectangle.