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1.若2x+5y-3=0,求4的x次方乘以32的y次方2.已知5的m次方=2,25的m+n次方=7,求5的5m+2n次方

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1.若2x+5y-3=0,求4的x次方乘以32的y次方2.已知5的m次方=2,25的m+n次方=7,求5的5m+2n次方的值3.已知x-2y=12,xy=-25,求x平方+4y平方-1的值4.已知x平方-2x=2,将下式先化简,再求值:(x-1)平方+(x+3)(x-3)+(x-3)(x-1)崩溃了 要初一学过的方法..
(1)
4^x*32^y
=2^(2x+5y)
=2^3
=8
(2) 5^(5m+2n)
=5^5m*5^2n
=5^m*5^4m+5^2n
=5^m*25^(2m+n)
=2*7
=14
(3)x²+4y²-1
=(x-2y)²+4xy-1
=12²-100-1
=43
(4) x²-2x=2
(x-1)²+(x+3)(x-3)+(x-3)(x-1)
=x²-2x+1+x²-9+x²-4x+3
=3x²-6x-5
=3(x²-2)-5
=6-5
=1