1.已知(x+√(x^2+2002))*(y+√(y^2+2002))=2002,求x^2-3xy-4(y^2)-6x-6y+58的值.2.如果a+b-2√(a-1)-4√(b-2)=3√(c-3)-c/2-5,求a+b+c的值.√的意思为根号
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![1.已知(x+√(x^2+2002))*(y+√(y^2+2002))=2002,求x^2-3xy-4(y^2)-6x-6y+58的值.2.如果a+b-2√(a-1)-4√(b-2)=3√(c-3)-c/2-5,求a+b+c的值.√的意思为根号](/uploads/image/z/14109318-54-8.jpg?t=1.%E5%B7%B2%E7%9F%A5%28x%2B%E2%88%9A%28x%5E2%2B2002%29%29%2A%28y%2B%E2%88%9A%28y%5E2%2B2002%29%29%3D2002%2C%E6%B1%82x%5E2-3xy-4%28y%5E2%29-6x-6y%2B58%E7%9A%84%E5%80%BC.2.%E5%A6%82%E6%9E%9Ca%2Bb-2%E2%88%9A%28a-1%29-4%E2%88%9A%28b-2%29%3D3%E2%88%9A%28c-3%29-c%2F2-5%2C%E6%B1%82a%2Bb%2Bc%E7%9A%84%E5%80%BC.%E2%88%9A%E7%9A%84%E6%84%8F%E6%80%9D%E4%B8%BA%E6%A0%B9%E5%8F%B7)
1.已知(x+√(x^2+2002))*(y+√(y^2+2002))=2002,求x^2-3xy-4(y^2)-6x-6y+58的值.2.如果a+b-2√(a-1)-4√(b-2)=3√(c-3)-c/2-5,求a+b+c的值.√的意思为根号
1.已知(x+√(x^2+2002))*(y+√(y^2+2002))=2002,求x^2-3xy-4(y^2)-6x-6y+58的值.
2.如果a+b-2√(a-1)-4√(b-2)=3√(c-3)-c/2-5,求a+b+c的值.
√的意思为根号
1.已知(x+√(x^2+2002))*(y+√(y^2+2002))=2002,求x^2-3xy-4(y^2)-6x-6y+58的值.2.如果a+b-2√(a-1)-4√(b-2)=3√(c-3)-c/2-5,求a+b+c的值.√的意思为根号
1.(x+√(x^2+2002))*(y+√(y^2+2002))=2002 两边同乘x-√(x^2+2002) -2002(y+√(y^2+2002))=2002(x-√(x^2+2002))
两边同乘(y-√(y^2+2002)) -2002(x+√(x^2+2002))=2002(y-√(y^2+2002))
两式相加 x+y=0
x^2-3xy-4(y^2)-6x-6y+58
=(x-4y)(x+y)-6(x+y)+58
=58
2.设x=√(a-1),y=√(b-2),z=√(c-3)则
a=x^2+1,b=y^2+2,c=z^2+3,则
原式变形得
2(x-1)^2+2(y-2)^2+(z-3)^2=0
(x-1)^2,(y-2)^2,(z-3)^2均>=0
所以只有x=1,y=2,z=3
a=2,b=6,c=12
a+b+c=20
解毕
1. (x+√(x^2+2002))*(y+√(y^2+2002))=2002 两边同乘x-√(x^2+2002) -2002(y+√(y^2+2002))=2002(x-√(x^2+2002))
两边同乘(y-√(y^2+2002)) -2002(x+√(x^2+2002))=2002(y-√(y^2+2002))
两式相加 x+y=0
x^2-3xy-4(y^2)-6x-6y+58
=(x-4y)(x+y)-6(x+y)+58
=58