我来献丑。
解:
因为 ( t --> -1 ) lim { x } = ∞ , ( t --> -1 ) lim { y } = ∞
而 k = ( t --> -1 ) lim { y/x } = ( t --> -1 ) lim { t } = -1
b = ( t --> -1 ) lim { y - kx } = ( t --> -1 ) lim { ( 3 * t^2 + 3 * t )/ (1+t^3)}
= ( t --> -1 ) lim { ( 3 * t )/ (1 - t + t^2 )} = -1
故有 渐近线方程 y = k x + b = - x - 1
即 x + y + 1 = 0