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

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प्रश्न

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

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उत्तर

f (x) = |x|, g(x) = sin x

f : R → (0, ∞) ; 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|

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|)

= sin |x|

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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 1.3 | पृष्ठ ५४

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