作业帮given the sum of two number is 20,find the minimum value of the sum of the squares of these two numbersAOB的面积是9 sq.units,求k的值,k大于1
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given the sum of two number is 20,find the minimum value of the sum of the squares of these two numbersAOB的面积是9 sq.units,求k的值,k大于1
given the sum of two number is 20,find the minimum value of the sum of the squares of these two numbers
AOB的面积是9 sq.units,求k的值,k大于1
given the sum of two number is 20,find the minimum value of the sum of the squares of these two numbersAOB的面积是9 sq.units,求k的值,k大于1
1.Given the sum of two number is 20,find the minimum value of the sum of the squares of these two numbers
Assume x+y=20 x^2+y^2=(x+y)^2-2xy=400-2xy
xy≤[(x+y)/2] If and only if x=y (xy)max=100
The minmum of x^2+y^2=400-100*2=200
（均值不等式）
Assume a number x,another number is 20-x
y=x^+(20-x)^2=2x^2-40x+400
Min(y)=200
（二次函数）
2.If x=0,y=2k
If y=0 x=-2k/(k-1)
BO=2k
AO=2k(k-1)
BO*AO=(4k^2)/(k-1)=2x9 k=3/2 or k=3