Question

what is the amplitude of the sinusoid given by y=-5sin (7x)

Answer 1

Hey there!

To start, the amplitude of a sinusoidal function is always the absolute value of the value in front of the sin. 

In the equation y=-5sin(7x), the A value,  is -5. 

Because your amplitude is the absolute value of this value, the amplitude of y=-5sin(7x) would be 5.

Hope this helps and have a wonderful day! :)

Answer 2

Hello there!

y = -5sin(7x)

Use the form y = Asin(Bt + C) + D

We know that |A| is the amplitude, thus, the amplitude is 5

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Why not -5

The reason is because we solved for the absolute value.

|A|


|-5| = 5

Thus,

The answer is: 5

As always, I am glad to help you tonight!!