lim(x→∞)【（√ x²+x）-（2√ 2x²+2x）+x】等于多少?题中x²+x和2x²+2x都在根号下

lim(x→∞)【（√ x²+x）-（2√ 2x²+2x）+x】等于多少?题中x²+x和2x²+2x都在根号下
lim(x→∞)【（√ x²+x）-（2√ 2x²+2x）+x】等于多少?
题中x²+x和2x²+2x都在根号下

lim(x→∞)【（√ x²+x）-（2√ 2x²+2x）+x】等于多少?题中x²+x和2x²+2x都在根号下
整理一下,提个公因式.其它的都是常规办法
详见参考资料.

lim(x→-∞){[1-2^(3/2)]√ (x^2+x) + x} = -无穷
lim(x→+∞){[1-2^(3/2)]√ (x^2+x) + x}
=lim(x→+∞){[1-2^(3/2)]^2 (x^2+x) - x^2}/{[1-2^(3/2)]√ (x^2+x) - x}
=lim(x→+∞)【{[1-2^(3/2)]^2-1}x^2 + x[1-2^(3/...

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lim(x→-∞){[1-2^(3/2)]√ (x^2+x) + x} = -无穷
lim(x→+∞){[1-2^(3/2)]√ (x^2+x) + x}
=lim(x→+∞){[1-2^(3/2)]^2 (x^2+x) - x^2}/{[1-2^(3/2)]√ (x^2+x) - x}
=lim(x→+∞)【{[1-2^(3/2)]^2-1}x^2 + x[1-2^(3/2)]^2】/ {[1-2^(3/2)]√ (x^2+x) - x}
=lim(x→+∞)【{[1-2^(3/2)]^2-1}x + [1-2^(3/2)]^2】/ {[1-2^(3/2)]√ (1+1/x) -1}
=-无穷
lim(x→∞){[1-2^(3/2)]√ (x^2+x) + x} = -无穷

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lim(x→∞){[1-2^(3/2)]√ (x^2+x) + x} = -无穷