Question

the height y of a ball thrown by a child is given by y = -1/12x^2 + 2x + 4. how high is the ball when it is at its maximum height

Answer 1

The height of ball when it is at maximum height is 12 unit

Explanation:

Given as :

A ball is thrown by child to height y

And y as a function x is y =
`-(1)/(12)x^(2)+2x+4`

So, for maximum value of height ,

`(\partial y)/(\partial x)` = 0

Or ,
`(\partial (-(1)/(12)x^(2)+2x+4))/(\partial x)` = 0

Or,
`-(1)/(12)(2x)+2` = 0

Or,
`(1)/(12)(2x)` = 2

or, x = 12

Hence The height of ball when it is at maximum height is 12 unit Answer