If x^4 + y^4 = 100 greatest value of x is between
A. 0 and 3
B. 3 and 6
C. 6 and 9
D. 9 and 12
E. 12 and 15
The answer has to be either A or B, but which would you choose.
To the power 4
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Yes the right answer is B between 3 to 6, but I am not sure how. Because if you take 4 4^4 is above 100.
However if you take x as 3.1, then x^4 = 92.351 which is still less than 100, and then y can taka a value such that y^4 added to x^4 can be 100. May be that is why the answer is B.
However if you take x as 3.1, then x^4 = 92.351 which is still less than 100, and then y can taka a value such that y^4 added to x^4 can be 100. May be that is why the answer is B.
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IMO Bsakurle wrote:If x^4 + y^4 = 100 greatest value of x is between
A. 0 and 3
B. 3 and 6
C. 6 and 9
D. 9 and 12
E. 12 and 15
The answer has to be either A or B, but which would you choose.
to maximize x^4 minimize y^4
y=0
for x=3, x^4=81
for x=4, x^4= 256
so x must be greater than 3 but less than 4
only B satisfies this
The powers of two are bloody impolite!!