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4 years ago

11

If sin theta = -1/2 and lies in the third quadrant, what is the cos?

1 answer:

never [62]4 years ago

5 0

Sin angle that equals the 1/2 value is the 30 degree on the 1st Quadrant.

The angle of 30 degree on the 3rd Quadrant is equivalent to (formula and circle in the 1st photo) 180 + 30 = 210°.

So theta = 210° (3rd Quadrant) = 30° (1st Quadrant).

$cos \: 30\degree = \sqrt{3} \div 2$

Now just transfer the cos 30° to the 3rd Quadrant and the signal will be negative (as shown in the 2nd photo attached).

$cos \: 210 \degree = - \sqrt{3} \div 2$

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Outside temperature over a day can be modeled as a sinusoidal function. Suppose you know the temperature is 80 degrees at midnig

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Answer:

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Step-by-step explanation:

Sine function:

Has the following format:

$y = A\sin{bx}$

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Answer:

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