早教吧 育儿知识 作业答案 考试题库 百科 知识分享

计算:(1+0.43+0.29)×(0.43+0.29+0.87)-(1+0.43+0.29+0.87)×(0.43+0.29)

题目详情
计算:(1+0.43+0.29)×(0.43+0.29+0.87)-(1+0.43+0.29+0.87)×(0.43+0.29)
▼优质解答
答案和解析
令0.43+0.29=x,
则(1+0.43+0.29)×(0.43+0.29+0.87)-(1+0.43+0.29+0.87)×(0.43+0.29)
=(1+x)(x+0.7)-x(1+x+0.87)
=x2+1.7x+0.7-x2-1.87x
=0.7-0.17x
=0.7-0.17×(0.43+0.29)
=0.7-0.17×0.72
=0.7-0.1224
=0.5776