# If the equation of projection is #y=ax-bx^2#, find initial velocity(#u#) and angle of projection(#theta#)?

##### 2 Answers

Given that the equation of projection is

Horizontal component of velocity of projection is

Vertical component of velocity of projection is

Let at the t th sec after its projection from origin its position be represented by the coordinates

So

Again

Combining [1] and[2] we get

Comparing equation [3] with the given equation we get

and

See below.

#### Explanation:

This is a typical kinematic problem. Assuming that the movement begins at the referential origin we have

where

Now the orbit equation is

This condition must be true for all

Now grouping coefficients

Now solving for

Now