Question

The equation h = 7 * cos((PI / 3) * t) models the height h in centimeters after t seconds of a weight attached to the end of a spring that has been stretched and then released.


a. Solve the equation for t.

Answer 1

I don't know how to get the t out of the cosine function. Do I use acos() or something?

Answer 2

Try and Isolate t by taking away the operations and functions attached to it by doing the inverse

Answer 3

That's the part I do not understand how to do right.

Answer 4

\[h = 7 Cos (\frac{ \pi }{ 3}t)\]\[Cos (\frac{ \pi }{ 3 }t) = \frac{ h }{ 7 }\]\[(\frac{ \pi }{ 3 }t) = \cos^{-1} (\frac{ h }{ 7 })\]\[t = \frac{ 3 }{ \pi }\cos^{-1} (\frac{ h }{ 7 })\]

Answer 5

Ok. I just made it overcomplicated. So for similar problems like h = sin(3x) I would so arcsin(h) = 3x?

Answer 6

yes

Answer 7

Thanks!

Answer 8

Then divide by 3 on both sides to isolate the x

Answer 9

so it will be 1/3 arcsin (h)

Answer 10

Ok. Thanks for your help!