Question

An objects motion is described by the equation d= 4sin (pi t) what will the height of the object be at 1.75 seconds?

Answer 1

Answer: 0.38 Meters

Explanation:

plug 1.75 in for t and solve, do not convert into units as you need the height so meters is accurate.

d=0.38

Answer 2

-2√2, or ≈-2.83

Explanation:

Well, when t = 1.75, our equation should be
`d=4sin((\pi \cdot1.75))`.

Note that
`\pi\cdot1.75=(7\pi)/(4)`. Using the unit circle (attached), we can find that the value of sine at
`(7\pi)/(4)` radians is exactly
`-(\sqrt2)/(2)`. Plugging that value back into our equation gives us

`d=4\cdot\left(-(\sqrt2)/(2) \right)=-(4\sqrt2)/(2)=-2\sqrt2`

So our answer is
`d=-2\sqrt2`, in whatever units we're using to measure height.