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If f(x) = 2x2 + 3, g (x) = 5x − 2, then find f ° g

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Question

If f(x) = 2x2 + 3, g (x) = 5x − 2, then find f ° g

Sum
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Solution

f(x) = 2x2 + 3, g(x) = 5x − 2

(f ° g) (x) = f[g(x)]

=f(5x − 2)

= 2(5x − 2)2 + 3

= 2(25x2 − 20x + 4) + 3

= 50x2 − 40x + 11.

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Chapter 6: Functions - Exercise 6.2 [Page 127]

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