已知命题:方程有两个不相等的负实根,命题:方程无实根;若或为真,且为假,求实数的取值范围.
灵活计算,能简便计算的要简算 3.4×5.9+5.9×6.654+99×99+45﹣(+)
递等式计算,能简算的要简算: 9.7﹣22.78÷3.41.05÷0.7+18.90.4×5÷0.4×5 21÷0.25÷0.40.125×32×0.2582.2×9.9.
脱式计算(能简算的要简算,没简算的不给分). 1.6×55.4﹣55.4×0.6﹣55.4 17.68÷5.2+2.7×1.5 4.8×0.25.
计算,能简算的要简算. 3.25×0.45+6.75×0.45 7.5×102 5.64÷0.125÷8 26.9×0.48÷2.695.4×2.5×0.739.5×99+39.5.
怎样简便怎样算. 7.28﹣(0.8+3.28)3.15+1.83+6.85+2.1713.86﹣2.99 13.92﹣(3.92﹣2.74)2.72﹣3.98+5.28﹣2.020.27﹣4.9+4.83+2.9.