2 years ago

Prove that cos^4∆ - sin^4∆ = 2cos^2∆ - 1

1 answer:

3 0

$\cos^{4} x-\sin^{4} x\\\\=(\cos^{2} x+\sin^{2} x)(\cos^{2} x-\sin^{2} x)\\\\=\cos^{2} x-\sin^{2} x\\\\=\cos^{2} x-(1-\cos^{2} x)\\\\=2\cos^{2} x-1$

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timama [110]

Answer:

area = 110.72 m²

Step-by-step explanation:

area of square = 8 x 9 = 72 m²

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4 0

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mezya [45]

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7 0

3 years ago

Find the domain of f(x)= square root of x + 5

Semenov [28]

Answer:

$\sqrt{x + 5}$

it's 1 since X has an invisible 1 infront of it...plus domain means X and Range means Y

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3 years ago

Solve for t. You must write your answer in fully simplified form.<br> -7t = 18

Musya8 [376]

Answer: t = -18/7 = 2.57

Step-by-step explanation:

-Solve for t:

$-7t=18$

$\frac{-7t}{-7} = \frac{18}{-7}$

$t=-\frac{18}{7} =2.57$

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4 years ago

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SOVA2 [1]

Answer:

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Since we want to know the number of oil changes in 11 days, we multiply the unit rate by 11 days.

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3 years ago