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Find Fog And Gof If : F(X)= X + 1, G (X) = 2x + 3 . - Mathematics

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प्रश्न

Find fog and gof  if : f(x)= x + 1, g (x) = 2x + 3 .

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उत्तर

f (x) = x+1, g (x) = 2x + 3

f : R→R ; g : R → R

Computing fog :

Clearly, the range of g is a subset of the domain of f.

⇒ fog : R→ R

(fog) (x) = f (g (x))

= f (2x+3)

= 2x + 3 + 1

= 2x + 4

Computing gof :

Clearly, the range of f is a subset of the domain of g.

⇒ fog : R → R

(gof) (x) = g (f (x))

= g (x+1)

= 2 ( x + 1) + 3

= 2x + 5

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अध्याय 2: Functions - Exercise 2.3 [पृष्ठ ५४]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 2 Functions
Exercise 2.3 | Q 1.7 | पृष्ठ ५४

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