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3 years ago

14

The school student council sponsored a Switch Day where students were able to switch classes every 20 minutes. The students are

in school for 7 hours. If a student switched as often as possible, how many classrooms in all did that student visit? (Hint there are 60 minutes in 1 hour)

1 answer:

zavuch27 [327]3 years ago

5 0

21 classes, because if the school hours are 7 hours long it would be 21 classes

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2 years ago

Trig proofs with Pythagorean Identities.

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To prove:

$$\frac{1}{1-\cos x}-\frac{\cos x}{1+\cos x}=2 \cot ^{2} x+1$

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Using the identity: $1=\cos ^{2}(x)+\sin ^{2}(x)$

$$=\frac{\cos ^{2}x+\cos ^{2}x+\sin ^{2}x}{\sin ^{2}x}$

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$$=1+2\frac{\cos^{2} x}{\sin^{2} x}$

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Equation (1) = Equation (2)

LHS = RHS

$$\frac{1}{1-\cos x}-\frac{\cos x}{1+\cos x}=2 \cot ^{2} x+1$

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4 years ago

Please help me with this problem !!!!!!

iren [92.7K]

Answer:

see explanation

Step-by-step explanation:

Given

s(t) = 10t²

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3 years ago