A sum of Rs. 2000 amounts to Rs. 4000 in two years at compound interest. In how many years does the same amount becomes Rs. 8000.

If cosθ/1-sinθ + cosθ/1+sinθ = 4 then

the value of θ(0<θ<90⁰) is

Suppose that the medians BD, CE and AF of a triangle ABC meet at G. Then AG: GF is

If in ΔABC, DE ||BC, AB = 7.5cm, BD = 6cm and DE = 2cm, then the length of BC in cm is :

If 9x² + 16y² = 60  and 3x + 4y = 6, then the value of xy is

Options:

If x = √2+1, then the value of x4-1/x4 is