The upper part of a tree broken over by the wind make an angle of 60 deg with the ground. The distance between the root and the point where top of the tree touches the ground is 25 metres. What was the height (in metres) of the tree?

On walking 100 metres towards a building in a horizontal line, the angle of elevation of its top changes from 45 to 60 deg. What will be the height (in metres) of the building?

What is the value of [cos (90 + A)÷sec (270 – A)] + [sin (270 + A)÷cosec (630 – A)]?

What is the value of sin (90° + 2A)[4 – cos2(90° – 2A)]?

What is the value of [2 sin (45 + θ) sin (45 – θ)]/cos 2θ?

What is the value of [(cos 3θ + 2cos 5θ + cos 7θ)÷(cos θ + 2cos 3θ + cos 5θ)] + sin 2θ tan 3θ?

What is the value of sin 75°+ sin 15°?

What is the value of [1 – sin (90 – 2A)] / [1 + sin (90 + 2A)]?