Question

pls help
it's urgent actually
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Answer 1

The incorrect one is (c)

Step-by-step explanation:

Lets analyse it by rearranging the expressions.

(a)

$a = \frac{2(s - ut)}{t^{2} } \\ at^{2} = 2s - 2ut \\ 2ut + at^{2} = 2s \\ \frac{2ut + at ^{2} }{2} = s \\ \frac{2ut}{2} + \frac{ at^{2}}{2} = s \\ ut + \frac{at^{2} }{2} = s$

(b)

$u = \frac{2s - at^{2} }{2t} \\ 2ut = 2s - at^{2} \\ 2ut + at^{2} = 2s \\ \frac{2ut + at^{2} }{2} = s \\ \frac{2ut}{2} + \frac{at^{2} }{2} = s \\ ut + \frac{at^{2} }{2} = s$

(c)

$t = \sqrt{ \frac{2s}{2u + a} } \\ t^{2} = \frac{2s}{2u + a} \\ 2ut^{2} + at^{2} = 2s \\ \frac{2ut^{2} }{2} + \frac{at^{2} }{2} = s \\ ut^{2} + \frac{at ^{2} }{2} = s$

(d)

$2s - 2ut = at^{2} \\ 2s = 2ut + at^{2} \\ s = \frac{2ut + at^{2} }{2} \\ s = \frac{2ut}{2} + \frac{at^{2} }{2} \\ s = ut + \frac{at^{2} }{2}$

So, The only expanded expression which doesn't satisfy the requirements in the question is option (c)

So, (c) is the wrong Answer