Find the sum of the first 18 terms of the series 3, 6, 9, -, -, -, 36.

Solve the inequality ${{x}^{2}}+2x>15$

Solve the inequality $-6(x+3)\le 4(x-2)$

T varies inversely as the cubes of R, when R =3, T = $\tfrac{2}{81}$, find T when R = 2

If x varies directly as square root of y and x = 81 when y =9, find x when y = $1\tfrac{7}{9}$

Solve for x and y respectively in the simultaneous equations$\begin{align}  & -2x-5y=3 \\ & x+3y=0 \\\end{align}$

Factorize completely $9{{y}^{2}}-16{{x}^{2}}$

Find the remainder when ${{x}^{3}}-2{{x}^{2}}+3x-3$is divided by ${{x}^{2}}+1$

Make R the subject of the formula if  $T=\frac{K{{R}^{2}}+M}{3}$