Consider the following statement is $S$ and $R$ ;

$S$. Both $\sin x$ and $\cos x$ are decreasing function in the interval $\left(\dfrac {\pi}{2}, \pi \right)$

$R:$ If a differentiable function decreases in an interval $(a, b)$ then its derivative also decreases in $(a, b)$, which of the following is true?

lf $\mathrm{f}(\mathrm{x})$ is a quadratic expression which is positive for all real vaues of $\mathrm{x}$ and $\mathrm{g}(\mathrm{x})=\mathrm{f}(\mathrm{x})+\mathrm{f}'(\mathrm{x})+\mathrm{f}''(\mathrm{x})$ then for any real value of $\mathrm{x}$

$x$ এর যে কোন মানের জন্য একটি বক্ররেেখার ঢাল $\frac{d y}{d x}=2 x$.

নিচের কোনটি (2, 5) বিন্দুতে বক্ররেখার সমীকরণ?

If $f (x)$ is differentiable everywhere, then: