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If XY is not equal to 0, x + y is not equal to 0, and 1 / x + 1 / y is positively proportional to x ^ 2 + y ^ 2, then (x + y) ^ 2 and x ^ 2 + y ^ 2 If XY is not equal to 0, x + y is not equal to 0, and 1 / x + 1 / y is inversely proportional to x ^ 2 + y ^ 2, then (x + y) ^ 2 and x ^ 2 + y ^ 2
Because: x ^ 2 + y ^ 2 = (x + y) ^ 2-2
So: (x + y) ^ 2 is proportional to x ^ 2 + y ^ 2
If XY is not equal to 0, x + y is not equal to 0, and 1 / x + 1 / y is inversely proportional to x ^ 2 + y ^ 2, then (x + y) ^ 2 and x ^ 2 + y ^ 2
What is the relationship between (x + y) ^ 2 and x ^ 2 + y ^ 2? Is it positive or negative?
It is proportional when XY is greater than zero and inversely proportional when XY is less than zero
Parametric equation of curve xy = 1
A. X = T ^ 1 / 2 y = T ^ 1 / 2 B x = Tana y = 1 / Tana I want to know how a is wrong
Xy = 1 can take value in one or three quadrants, a can only have value in one quadrant
Why do the parametric equations x = T ^ 2 and y = T ^ - 2 and xy = 1 not represent the same curve?
xy=1 x≠0 y≠0
The parametric equations x = T ^ 2 > 0 and y = T ^ (- 2) > 0
So it doesn't mean the same curve
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