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3 years ago

13

I NEED HELP PLEASE!!!

1 answer:

solmaris [256]3 years ago

7 0

Answer:

C

Step-by-step explanation:

cos(theta) is positive in IV quadrant and sin(theta)=sqrt(13^2-5^2)/13=-12/13

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Step-by-step explanation:

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Answer:

Option A is correct.

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Step-by-step explanation:

Given that : $2\cos^2x -\cos x -1 =0$

Let $\cos x =y$

then our equation become;

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A quadratic equation is of the form:

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then;

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Simplify:

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Step-by-step explanation:

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