1 year 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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Which ratio forms a proportion with 18/27

JulsSmile [24]

Answer:

$\frac{2}{3}$

Step-by-step explanation:

The given ratio is $\frac{18}{27}$

9 is the common factor of 18 and 27

divide numerator and denominator by 9

$\frac{18/9}{27/9} =\frac{2}{3}$

hence $\frac{2}{3}$ is proportion with $\frac{18}{27}$

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Shkiper50 [21]

Answer:

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Step-by-step explanation:

let w represent width then length l = 3w - 3

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6w - 6 + 2w = 210

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8w = 216 ( divide both sides by 8 )

w = 27 and l = 3(27) - 3 = 81 - 3 = 78

Then length = 78 m and width = 27 m

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You have 480 feet of fencing to enclose a rectangular garden. you want the length of the garden to be 30 feet greater than the w

lesya692 [45]

The length is 135 ft

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What are the intercepts of 3x -4y=-24

masha68 [24]

Answer:

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Read 2 more answers

Simplify the expression 9m-7m+2m

tatuchka [14]

Simplify step-by-step.

9m−7m+2m

=9m+−7m+2m

Combine Like Terms:

=9m+−7m+2m

=(9m+−7m+2m)

=4m

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2 years ago