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Discussion Response Post to: plz solve this

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Titun (1467)

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f ' (x) = g (x)

g ' (x) = - f (x)

Consider a function

h (x) = [ f (x) ] ² + [ g (x) ] ²

Therefore, h ' (x) = 2 f (x) . f ' (x) + 2 g(x). g ' (x) = 2 f (x). g(x) - 2 g(x). f (x) = 0

Hence, h (x) is a constant function and so the value of h (2) will be the same as the value of h (16)

h (2) = [ f (2) ] ² + [ g (2) ] ² = [ f (2) ]² + [ - f (2) ] ² = 4² + 4²= 32
h (2) = h (16) = 32

So, h (16) = [ f (16) ] ² + [ g (16) ] ² = 32

Cheers!

You never know what is enough till you know what is more than enough. Titun

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