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प्रश्न
Derive the equation
V2-u2 = 2as
उत्तर
In figure we know
S = area of trapezium OSQP
Area of trapezium OSQP = `1/2` {sum of parallel sides) x perpendicular distance between them.
S = `1/2` (OP + SQ) x PR.
PR= QR/a= (QS - RS) / a
PR= (v - u)/a = t
So PR= t .
Substituting these values in expression of area of trapezium we get S= Y. {u + v) x t S = `1/2 (u +v) x (u - v)/a.
2aS = v2 - u2
v2 - u2 = 2 as.
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