求证明极限lim(x,y)->(0,0) (x^2 * sin^2y)/x^2 +9y^2 =0如题,求证明该极限=0

问题描述:

求证明极限lim(x,y)->(0,0) (x^2 * sin^2y)/x^2 +9y^2 =0
如题,求证明该极限=0