Question

已知a的m＋n方＝6；a的3m＋2n方＝72求：a的m－n方的值

Answer 1

1：a^（3m+2n)=72
2：a^(m+n)=6
1式除晌橡2的宴旅旁平镇兄方得到：a^m=2
a^n=3
所以a（m-n）=2/3

Answer 2

a^(m+n)=6
a^m*a^n=6
a^2m*a^2n=36
所顷李以a^m*(a^2m*a^2n)=a^(3m+2n)
36a^m=72
a^m=2
2a^n=6
a^n=3

所雀茄迟以a^(m-n)=a^m/纳蠢a^n=2/3

Answer 3

a^(m-n)=a^(6m+4n-5m-5n)=a^(2(3m+2n)-5(m+n))
=a^2(3m+2n)/a^5(m+n)
=72^2/卜敬悔6^5
=(2*6^2)^2/稿粗6^5
=4*6^4/6^5
=4/6
=2/型正3

Answer 4

a^(m+n)=6
a^(3m+2n)=72

a^m=a^(3m+2n)÷a^2(m+n)=72÷(6^2)=2
a^n=a^3(m+n)÷a^(3m+2n)=6^3÷72=3

a^(m-n)=a^m÷a^n=2/橡知枝梁敏猛猜3

Answer 5

a^(m+n)=6
[a^(m+n)]^2=36
a^(2m+2n)=36
a^(3m+2n)=72
a^(3m+2n)/a^(2m+2n)=72/察态毁败备36
a^(3m+2n-2m-2n)=2
a^m=2
a^(m+n)=6
3^(m+n)/3^m=6/闭配2
3^(m+n-m)=3
3^n=3
3^(m-n)=3^m/3^n=2/3