The area $'A'$ of a blot of ink is growing such that after $t$ second its area is given by $A = (3t^2 + 7)\,cm^2$. Calculate the rate of increase of area at $t = 2\, sec$. .......... $cm^2/s$
If $\tan \theta=\frac{1}{\sqrt{5}}$ and $\theta$ lies in the first quadrant, the value of $\cos \theta$ is :
If $log_{10} (xy) = 2$, then the value of $xy$ is
The slope of graph as shown in figure at points $1,2$ and $3$ is $m_1, m_2$ and $m_3$ respectively then