Q1 of 215 Page 3

Find fog and gof, if

f(x) = ex, g(x) = logex

f(x) = ex and g (x) = loge x


Now, fog(x) = f(g(x)) = f(loge x) = elogex= x


⇒ fog(x) = x


gof(x) = g(f(x)) = g(ex) = loge ex = x


⇒ gof(x)=x


Hence, fog(x) = x and gof(x) = x


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