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3 years ago

Prove that sin alpha × sin(90- alpha) - cos(90-alpha) × cos alpha

Mathematics

1 answer:

satela [25.4K]3 years ago

8 0

Answer:

It is equal to 0.

Step-by-step explanation:

I can simplify it as follows:

sinα sin(90 - α) - cos(90 - α)(cosα)

Now sin(90 -α) = cosα and cos(90 - α) = sinα) ( for α < 90)

So the expression becomes:

sinαcosα - sinαcosα

= 0 .

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3 years ago

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olga_2 [115]

Answer:

The vehicle covers 126 miles on 7 gallons of fuel.

Step-by-step explanation:

Given:

The distance traveled is directly proportional to the amount of fuel.

For $F$ gallons of fuel distance traveled $D$ miles can be given as:

$D$ ∝ $F$

$D=kF$

where $k$ is constant of proportionality.

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$90=k(5)$

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2 years ago

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irakobra [83]

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the average person lives at least 1.9 years
maybe, I guess

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3 years ago

Read 2 more answers

Prove that sin alpha × sin(90- alpha) - cos(90-alpha) × cos alpha​

Prove that sin alpha × sin(90- alpha) - cos(90-alpha) × cos alpha