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The height in feet of a projectile is given by the function h(t) = -16t^2+20t+9 where t represents the time in seconds after launch. What is the maximum height reached by the projectile?

 May 3, 2020
 #1
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-16t^2  + 20t  + 9

 

Te time to reach the max height  can be found as

 

-20 / [ 2 * -16]  =   -20/ -32  =   5/8 sec

 

Putting this back into the function we find the max height as

 

-16(5/8)^2  + 20(5/8)  + 9  =

 

-16 ( 25/64) + 100/8  + 9  =

 

-400/64  + 100/8  + 9  =

 

-100/16 + 200/16 + 144/16 =   244/16  = 15.25 ft

 

 

cool cool cool

 May 3, 2020

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