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3 years ago

If θ is a first-quadrant angle in standard position with P(u, v) = (3, 4), evaluate cos 2 θ . -7/25 -1/5 7/25

Mathematics

1 answer:

Grace [21]3 years ago

6 0

Answer:

-7/25.

Step-by-step explanation:

From the given point P we see that the hypotenuse = √(3*2 + 4^2) = 5.

So cos θ = 3/5

cos 2 θ = 2 cos^2 θ - 1

= 2 * (3/5)^2 -1

= -7/25.

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Answer:

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Step-by-step explanation:

<em>The question is to find the lengths of 2 sides of the rectangle</em>.

<u>Solution:</u>

Let shorter side be "x"

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From the question, we can write:

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also

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Now, putting the first on second equation, we get:

y - x = 10

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Now, y = 3x, y = 3(5) = 15

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