Tìm các số nguyên x thỏa mãn :
a, \(\left(x-2\right)\left(x-7\right)< 0\)
b, \(\left(x^2-3\right)\left(x^2-10\right)< 0\)
c, \(\left(x^2-1\right)\left(x^2-4\right)\left(x^2-7\right)\left(x^2-10\right)< 0\)
d, \(\left(x^3+5\right)\left(x^3+10\right)\left(x^3+15\right)\left(x^3+30\right)< 0\)