131.

PQ is a direct common tangent of two circles of radii r₁ and r₂ touching each other externally at A. Then, the value of PQ² is

• r₁r₂

• 2r₁r₂

• 3r₁r₂

• 4r₁r₂

BC is the chord of a circle with centre O. A is a point on major arc BC as shown in the above figure. What is the value of ∠BAC + ∠OBC = ?

• 120°

• 60°

• 90°

• 180°

Two circles with radii 5 cm and 8 cm touch each other externally at a point A. If a straight line through the point A cuts the circles at points P and Q respectively, then AP : AQ is

• 8 : 5

• 5 : 8

• 3 : 4

• 4 : 5

If l is the in-centre of Δ ABC and ∠A = 60°, then the value of ∠BIC is

• 100°

• 120°

• 150°

• 110°

The external bisectors of ∠B and ∠C of Δ ABC meet at point P. If Δ BAC = 80°, then ∠BPC is

• 50°

• 40°

• 80°

• 100°

When a pendulum of length 50 cm oscillates, it produces an arc of 16 cm. The angle so formed in degree measure is (approx.)

• 18°25'

• 18°35'

• 18°20'

• 18°08'

If x, y are positive acute angles x + y < 90° and sin (2x - 20°) = cos (2y + 20°), then the values of sec (x + y) is

• 

• 

• 1

• 0

If 5 tan θ = 4,  then the value of  is

The least value of (4 sec²θ +  9 cosec²θ) is

• 1

• 19

• 25

• 7

If tan (x + y) tan (x - y) = 1,  then the value of  is

• 

• 

• 

• 1