A person from the top of a hill observes a vehicle moving towards him at a uniform speed. It takes 10 minutes for the angle of depression to change from 450 to 600.
After this the time required by the vehicle to reach the bottom of the hill is
If (a2-b2) sin θ + 2abcos θ = a2+b2, then tan θ =
If sec θ + tan θ=m (>1), then the value of sin θ is (00 < θ < 900)
If xsin3 θ + ycos3 θ = sin θ cos θ and xsin θ – ycos θ = 0, then the value of x2 + y2 equals
The value of the expression (1+sec220 + cot 680)(1-cosec220 + tan680) is
B1 is a point on the side AC of Δ ABC and B1B is joined. A line is drawn through A parallel to B1B meeting BC at A1 and another line is drawn through C parallel to B1B meeting AB produced at C1. Then