Evaluate lim(x,y)(0,0) 1cos(xy)x2y2(7+y)\displaystyle \lim_{{{\left({x},{y}\right)}\rightarrow{\left({0},{0}\right)}}}\ {\frac{{{1}-{\cos{{\left({x}{y}\right)}}}}}{{{x}^{{2}}{y}^{{2}}{\left({7}+{y}\right)}}}} =  

Use DNE for does not exist, oo for infinity or -oo for negative infinity.