qn 約1年以前 觀察:d/dx ( x²+2x-2 ) = 2x+2 = 2(x+1) 可知 d/dx (x²+2x-2)³ = 3(x²+2x-2)² · 2(x+1) 所以 ∫₀¹ (x+1)(x²+2x-2) dx = (x²+2x-2)³/6 |₀¹ = 1/6 - (-8/6) = 9/6 = 3/2 留言