Question

解不等式：k的3次方-3*k的平方+2>0

Answer 1

k³-3k+2>0

k³-k²+k²-k-2k+2>0

k²(k-1)+k(k-1)-2(k-1)>0

(k-1)(k²+k-2)>0

(k-1)(k+2)(k-1)>0

(k-1)²(k+2)>0

不等式解-2