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2 years ago

Use a double angle or half angle identity to find the exact value of each expression

Mathematics

1 answer:

inna [77]2 years ago

4 0

θ is given to be in the fourth quadrant (270° < θ < 360°) for which sin(θ) < 0 and cos(θ) > 0. This means

cos²(θ) + sin²(θ) = 1 ==> sin(θ) = -√[1 - cos²(θ)] = -3/5

Now recall the double angle identity for sine:

sin(2θ) = 2 sin(θ) cos(θ)

==> sin(2θ) = 2 (-3/5) (4/5) = -24/25

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Please help. 50 points + brainliest

Korvikt [17]

Answer:

1. (a-c) $\sqrt{x}$ + b $\sqrt{y}$

2. 9m + 2 $\sqrt{n}$

3. 6a

4. (5a - 3b) $\sqrt{5y}$

Step-by-step explanation:

1. since a and c share the same squareroot x, you can combine these together.

2. First add like terms together. 4m - m + 6m = 9m. Then 5 $\sqrt{n}$ and -3 $\sqrt{n}$ combined equals 2 $\sqrt{n}$

3. First simplify the square roots. squareroot of 16 is 4. square root of 49 is 7. square root of 81 is 9. They are all multiplied by a in the expression. Thus 4a - 7a + 9a = 6a

4. First simplify the radicals, they are not perfect. square root of 125 is equivalent to sqrt(25 * 5), which sqrt of 25 is 5, but we keep the sqrt of 5. For sqrt of 45, it is the same as sqrt9 * sqrt5. sqrt of 9 is the same as 3 and we keep sqrt 5. Thus we get the below:

5a $\sqrt{5y}$ - 3b $\sqrt{5y}$

We can combine the two like terms and get the final answer above.

please give thanks by clicking the heart :)

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3 years ago

The manager of a bookstore ordered 480 copies of a book. The manager paid a total of $7,440 for the books. The books arrived at

Neko [114]

So 48 • 4 would equal 192 so 4 • 2 mins equals 8 mins and then you have 8 more books to unpack so 48 divide by 8 equals 6. So the answer would bc (8 mins and 6 second)

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AnnZ [28]

Answer:

Lets isolate

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negate the right side

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Step-by-step explanation:

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