Solve for 0<=θ<π, the equation sin3θ-(sqrt3)cosθ=0 (C2)

Rearrange the equation to give sin3θ=(sqrt3)cos3θ, then divide through by cos3θ to give sin3θ/cos3θ=sqrt3. We know from our trig identities that sinx/cosx=tanx, so our equation now becomes tan3θ=sqrt3. Use your calculator to find 3θ, I got 3θ=π/3, so θ=π/9 which is within our range for θ.

BH

Related Maths A Level answers

All answers ▸

A level Maths question - The graph of y=2sin(2x)+1 is rotated 360 degrees about the x-axis to form a solid. Find the volume enclosed by the curve, the co-ordinate axes and the line x=pi/2


Draw the curve for x^2-5x+6


Integrate xsin(x) with respect to x


Sketch the graph of f(x) = sin(x). On the same set of axes, draw the graph of f(x)+2, f(2x) and f(-x). By observing your graphs of f(x) and f(x), if f(a)=1, what is the value of f(-a)?