If tan θ = tan 30° . tan 60° and θ is an acute angle , then 2θ is equal to

The compound interest on a certain sum for 2 yearsat 10% per annum isRs. 525 . The simple interest on the same sum for double the time at half the rate percent per annum is :

A straight tree breaks due to storm and the broken part bends so that the top of the tree touches the ground making an angle of 30° with the ground . The distance from the foot of the tree to the point , where the top touches the ground is 10 m. Find the total height of the tree

AB is a diameter of the circle with centre O , CD is chord of the circle , If ∠BOC = 120° , then the value of ∠ADC is

The ratio of circumradius and radius of an equilateral triangle is