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1.Relation and Function
easy
ધારો કે વિધેય :$f:\left[0, \frac{\pi}{2}\right]$ $ \rightarrow$ $R$, $f(x)=\sin x$ અને $g:\left[0, \frac{\pi}{2}\right] $ $\rightarrow$ $R$, $g(x)=\cos x$ દ્વારા આપેલ છે. સાબિત કરો કે $f$ અને $g$ એક-એક છે, પરંતુ $f+ g$ એક-એક નથી.
Option A
Option B
Option C
Option D
Solution
since for any two distinct elements $x_{1}$ and $x_{2}$ in $\left[0, \frac{\pi}{2}\right]$, $\sin x_{1} \neq \sin x_{2}$ and $\cos x_{1} \neq \cos x_{2},$ both $f$ and $g$ must be one-one. But $(f\,+\,g)(0)=\sin 0+\cos 0=1$ and $(f+g)\left(\frac{\pi}{2}\right)$ $=\sin \frac{\pi}{2}+\cos \frac{\pi}{2}=1 .$ Therefore, $f\,+\,g$ is not one-one.
Standard 12
Mathematics
