# Math

posted by
**Lisa** on
.

1)A piano tuner uses a tuning fork. If middle C has a frequency of 264 vibrations per second, write an equation in the form d=sinw(t) for the simple harmonic motion.

2) Verify the identity

tan^2X-cot^2X/tanX+cotX=tanX-cotX

I'm not completely sure on the first one, but I think it looks like

d=sin(264*t) Check your text for a worked example.

The second one is algebra.

[(tanX)^2-(cotX)^2]/[tanX+cotX]=tanX-cotX

or

[(tanX-cotX)(tanX+cotX)]/[tanX+cotX]=tanX-cotX

Can you finish it?