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Find Fog And Gof If : F (X) = X+1, G (X) = Sin X .

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प्रश्न

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

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उत्तर

f(x) = x+1, g(x) = sin x

f : R→R ; g : R→[−1, 1]

Computing fog :

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

⇒ fog: R→ R

(fog) (x) = f (g (x))

= f ( sin x )

= sin x + 1

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)

= sin ( x+1)

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अध्याय 2: Functions - Exercise 2.3 [पृष्ठ ५४]

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आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
अध्याय 2 Functions
Exercise 2.3 | Q 1.6 | पृष्ठ ५४

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