The angle of elevation of an aeroplane from a point on the ground is 45°. After flying for 15 seconds, the elevation changes to 30°. If the aeroplane is
flying at a height of 2500 metres, then the speed of the aeroplane in km/hr. is
1). 600
2). $600(\sqrt{3}+1)$
3). $600\sqrt{3}$
4). $600(\sqrt{3}-1)$
2. If cosec 135° = x, then the value of x is
4. Find the Minimum value of 9 cos 2x + 2 sec 2x
6. If Sin A + Cos A = 0.5, find the value of Sin A.Cos A = ?
7. ΔPQR is right angled at Q. If ∠P = 60°, then find the value of (cotR + √3/2).
8. If sin 3A = $cos( A - 26^{0})$, where 3A to an acute angle then the value of A is
9. What should be the missing digit so that the number 275_476 becomes exactly divisible by 11?