Question

求极限limx趋向于负无穷(根号下4x^2+x-1)+x+1/(根号下x^2+sinx)

Answer 1

简单计算一下即可，答案如图所示

Answer 2

linx->-∞√4x^2+x-1 +x+1/√x^2+sinx===>linx->-∞(√4x^2/x^2+x/x^2-1/X^2 +x/x+1/x)/(√x^2/x^2+sinx/x^2)
=linx->-∞(√4+1/x-1/x^2 +1+1/x)/(√1+sinx/x^2)=linx->-∞(√4+1)/√1=5