问题
解答题
(-5x2-1)(2x2-3),其中x=2.
答案
(-5x2-1)(2x2-3)=-10x4+15x2-2x2+3=-10x4+13x2+3,
当x=2时,
原式=-10×24+13×22+3=-10×16+13×4+3=215;
(-5x2-1)(2x2-3),其中x=2.
(-5x2-1)(2x2-3)=-10x4+15x2-2x2+3=-10x4+13x2+3,
当x=2时,
原式=-10×24+13×22+3=-10×16+13×4+3=215;