Question

Find the centre of gravity of an area of cardioide r=(1+cos tetha) .

Answer 1

Answer:

l=∫√r2+(drdθ)2dθ. r=1+cos θ⇒drdθ=−sinθ. l=2∫π0√(1+cosθ)2+sin2θdθ . l=2∫π0√1+2cosθ+cos2θ+sin2θdθ.