First we use sin(a+b)= sinacosb+sinbcosa
and cos(a+b)=cosa cosb -sinasinb
tan(x+pi/2)= sin(x+pi/2) / cos(x+pi/2)
and sin(x+pi/2) = sinxcospi/2 + sinpi/2cosx =cosx,
<span>cos(x+pi/2) = cosxcospi/2- sinxsinpi/2= - sinx,
</span> because <span>cospi/2 =0, </span>and <span>sinpi/2=1
</span><span>=tan(x+pi/2)= sin(x+pi/2) / cos(x+pi/2)= cosx / -sinx = -1/tanx = -cotx
</span>from where <span>tan(x+pi/2)=-cotx</span>
The first thing we must do is calculate the circumeference:
now, calculate the angle of arc
360° = 49.612
360° - 66.4° - 180° = x
x = 113.6°
now, to calculate the arc length it would be:
There are 1 1/2 hip hop classes for 1 ballet class.
Ok I’m im not sure you can ask someone else sorry
