Question #ec169

1 Answer
Feb 14, 2018

#int_(-2)^2 dx/sqrt(4-x^2)=pi#

Explanation:

#int_(-2)^2 dx/sqrt(4-x^2)#

After using #x=2sinu# and #dx=2cosu*du# transforms, this integral became

#int_(-pi/2)^(pi/2) (2cosu*du)/(2cosu)#

=#int_(-pi/2)^(pi/2) du#

=#[u]_(-pi/2)^(pi/2)#

=#pi#