用简便方法计算(初二的)
来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:数学作业 时间:2024/08/16 10:24:01
用简便方法计算(初二的)
(1)65^2 * 24 - 35^2 *24
(2)127^2 - 54 * 127 + 27^2
(1)最后得数是 72000 (2)最后得数是 10000
(1)65^2 * 24 - 35^2 *24
(2)127^2 - 54 * 127 + 27^2
(1)最后得数是 72000 (2)最后得数是 10000
![用简便方法计算(初二的)](/uploads/image/z/17953187-59-7.jpg?t=%E7%94%A8%E7%AE%80%E4%BE%BF%E6%96%B9%E6%B3%95%E8%AE%A1%E7%AE%97%EF%BC%88%E5%88%9D%E4%BA%8C%E7%9A%84%29)
1:65²×24-35²×24
=24×(65²-35²)
=24×(65-35)×(65+35)
=24×30×100
=72000
2:127²-54×127+27²
=127²-2×27×127+27²
=(127-27)²
=100²
=10000
=24×(65²-35²)
=24×(65-35)×(65+35)
=24×30×100
=72000
2:127²-54×127+27²
=127²-2×27×127+27²
=(127-27)²
=100²
=10000