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## Homework Statement

A particle is projected with a speed of 98 m s−1 at an angle A to the horizontal.

The range of the particle is 940·8 m. Find

(i) the two values of A

## The Attempt at a Solution

U = 98cosAi + 98sinAj

**i direction**

s = ut

940.8 = 98cosAt

**j direction**

s = ut + (0.5)at[itex]^{2}[/itex]

0= 98sinAt - (0.5)gt[itex]^{2}[/itex]

98sinA = gt/2

t = 20sinA

**i direction**

940.8 = (20sinA)(98cosA)

94.8 = (2sinAcosA)g

94.8 / g = sin2A

And I end up with a math error. Help please.