已知m,x,y满足:(1)(x-5)²+|m|=0,(2)-2ab(y平方)与4ab(3次方)是同类项.求代数

2个回答

  • 2/3(x-5)^2+5*(m的绝对值)

    是不是2/3(x-5)^2+5*(m的绝对值)=0?

    如果是则(x-5)^2>=0,所以2/3(x-5)^2>=0

    |m|〉=0,所以5*|m|>=0

    两个大于等于0的数相加等于0,若有一个大于0,则另一个小于0,不成立

    所以两个都等于0

    所以x-5=0,m=0

    x=5

    -2a^2b^(y+1)与3a^2b^3是同类项

    所以a和b的指数对应相等

    所以y+1=3,y=2

    0.375x^2y+5m^2x-{-7/16x^2y+[-1/4xy^2+(-3/16x^2y-3.475xy^2)]-6.275xy^2}

    =0.375x^2y+5*0^(2*5)-[-7/16x^2y+(-1/4xy^2-3/16x^2y-3.475xy^2)-6.275xy^2]

    =0.375x^2y+0-(-7/16x^2y-1/4xy^2-3/16x^2y-3.475xy^2-6.275xy^2)

    =0.375x^2y-(-5/8x^2y-10xy^2)

    =0.375x^2y+5/8x^2y+10xy^2

    =x^2y+10xy^2

    =5^2*2+10*5*2^2

    =50+200

    =250