If sinθ + sin2θ + sin3θ = 1, then cos6θ - 4cos4θ + 8cos2θ is
If \(sec\theta = x + {1\over 4x}\) (0° < θ < 90°), then secθ + tanθ is equal to
A is twice as good a workman as B and together they finish a piece of work in 13 days. In how many days will B alone finish the work?
Which of the following is true for 0° < θ < 90° ?
Pipes A, B and C can fill a tank in 15, 30 and 40 hours, respectively. Pipes A, B and C are opened at 6 a.m., 8 a.m. and 10 a.m., respectively, on the same day. When will the tank be full?