# Thread: Some trig qs - need help.

1. ## Some trig qs - need help.

1. Find exact value of

sin2pi/3

2. find the area enclosed between the curve y = cos2x, the x-axis and the lines x = -pi/6 and x = +pi/6

3. simplify:

lim 2tanx/x
x ->0

4. find the equation of the tangent to the curve y = sin3x at the point (pi/4, 1/sqroot2)

5. Use the trapezoidal rule with 4 subintervals to find an approximation to the volume of the solid formed by rotating the curve y= sqroot cosx about the x-axis from x = 0 to x =pi/2.

2. Originally Posted by MathsBeforeBedtime
1. Find exact value of

sin2pi/3

2. find the area enclosed between the curve y = cos2x, the x-axis and the lines x = -pi/6 and x = +pi/6

3. simplify:

lim 2tanx/x
x ->0

4. find the equation of the tangent to the curve y = sin3x at the point (pi/4, 1/sqroot2)

5. Use the trapezoidal rule with 4 subintervals to find an approximation to the volume of the solid formed by rotating the curve y= sqroot cosx about the x-axis from x = 0 to x =pi/2.
What have you tried? Where are you stuck? Apart from other things, there are too many questions here. Given the nature of these questions, please re-post more - one question per thread in the appropriate subforum and with all your working (say where you get stuck). See rule #8: http://www.mathhelpforum.com/math-he...ng-151418.html.