几道数学题``我不会做吖```谁会```1:已知:2^m=x,4^3m=y,要求用x的代数式表示y,则y= 2:已知a+1/a=4,求①a^2+1/a^2②a^4+1/a^4的值 3:已知:27^2=a^6=9^b, 化简(a- 1/5 b)^2 +(a+ 1/5 b)^2 +2b (a-1/25^b)并求值

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几道数学题``我不会做吖```谁会```1:已知:2^m=x,4^3m=y,要求用x的代数式表示y,则y= 2:已知a+1/a=4,求①a^2+1/a^2②a^4+1/a^4的值 3:已知:27^2=a^6=9^b, 化简(a- 1/5 b)^2 +(a+ 1/5 b)^2 +2b (a-1/25^b)并求值
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几道数学题``我不会做吖```谁会```1:已知:2^m=x,4^3m=y,要求用x的代数式表示y,则y= 2:已知a+1/a=4,求①a^2+1/a^2②a^4+1/a^4的值 3:已知:27^2=a^6=9^b, 化简(a- 1/5 b)^2 +(a+ 1/5 b)^2 +2b (a-1/25^b)并求值
几道数学题``我不会做吖```谁会```
1:已知:2^m=x,4^3m=y,要求用x的代数式表示y,则y=
2:已知a+1/a=4,求①a^2+1/a^2②a^4+1/a^4的值
3:已知:27^2=a^6=9^b,
化简(a- 1/5 b)^2 +(a+ 1/5 b)^2 +2b (a-1/25^b)并求值

几道数学题``我不会做吖```谁会```1:已知:2^m=x,4^3m=y,要求用x的代数式表示y,则y= 2:已知a+1/a=4,求①a^2+1/a^2②a^4+1/a^4的值 3:已知:27^2=a^6=9^b, 化简(a- 1/5 b)^2 +(a+ 1/5 b)^2 +2b (a-1/25^b)并求值
:已知:2^m=x,4^3m=y,要求用x的代数式表示y,则y= x^6
2:已知a+1/a=4,求①a^2+1/a^2②a^4+1/a^4的值
[a+1/a]^2=a^2+1/a^2+2=16
a^2+1/a^2=14
[a^2+1/a^2]^2=a^4+1/a^4+2=196
a^4+1/a^4=194
3:已知:27^2=a^6=9^b,
化简(a- 1/5 b)^2 +(a+ 1/5 b)^2 +2b (a-1/25^b)并求值
27^2=3^6=a^6=3^(2b)
a=3
b=3
上式=2a^2+2/25b^2+2ab-2/25b^2
=2a^2+2ab
=2*3*3+2*3*3=36

Y=4^3Log2^x

1.y=x^6
2.①10 ②82

1 y=2^6m=(2^m)^6=x^6
2 a^2+1/a^2=(a+1/a)^2-2=14
a^4+1/a^4=(a^2+1/a^2)^2-2=194
3 a=3 b=3
(a- 1/5 b)^2 +(a+ 1/5 b)^2 +2b (a-1/25^b)
=2a^2+2/25b^2+2ab-2/25b^2
=2a(a+b)
=2*3(3+3)
=36

^代表什么啊.?
我数学惨,路过。.