(lg2)²×lg250+(lg5)²×lg40
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/27 19:01:26
![(lg2)²×lg250+(lg5)²×lg40](/uploads/image/z/7110608-32-8.jpg?t=%EF%BC%88lg2%EF%BC%89%26%23178%3B%C3%97lg250%2B%EF%BC%88lg5%EF%BC%89%26%23178%3B%C3%97lg40)
(lg2)²×lg250+(lg5)²×lg40
(lg2)²×lg250+(lg5)²×lg40
(lg2)²×lg250+(lg5)²×lg40
(lg2)²lg250+(lg5)²lg40
=(lg2)²×(lg5²+lg10)+(lg5)²×(lg2²+lg10)
=(lg2)²×2lg5+(lg2)²+(lg5)²×2lg2+(lg5)²
=(lg2)²+2lg2lg5(lg2+lg5)+(lg5)²
=(lg2)²+2lg2lg5+(lg5)²
=(lg2+lg5)²
=(lg10)²
=1²
=1