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Answer the following: Find f ° g and g ° f : f(x) = x2 + 5, g(x) = x – 8

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Question

Answer the following:

Find f ° g and g ° f : f(x) = x2 + 5, g(x) = x – 8

Sum
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Solution

f(x) = x2 + 5, g(x) = x – 8

(f ° g) (x) = f[g(x)]

= f(x –  8)

= (x –  8)2 + 5

= x2 – 16x + 64 + 5

= x2 –  16x + 69

(g ° f) (x) = g[f(x)]

=g[x2 + 5)

= (x2 +5) –  8

= x2 – 3

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Chapter 6: Functions - Miscellaneous Exercise 6.2 [Page 130]

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Balbharati Mathematics and Statistics (Arts and Science) Part 2 [English] Standard 11 Maharashtra State Board
Chapter 6 Functions
Miscellaneous Exercise 6.2 | Q II. (12) (i) | Page 130

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