It looks like the differential equation is
Check for exactness:
As is, the DE is not exact, so let's try to find an integrating factor <em>µ(x, y)</em> such that
*is* exact. If this modified DE is exact, then
We have
Notice that if we let <em>µ(x, y)</em> = <em>µ(x)</em> be independent of <em>y</em>, then <em>∂µ/∂y</em> = 0 and we can solve for <em>µ</em> :
The modified DE,
is now exact:
So we look for a solution of the form <em>F(x, y)</em> = <em>C</em>. This solution is such that
Integrate both sides of the first condition with respect to <em>x</em> :
Differentiate both sides of this with respect to <em>y</em> :
Then the general solution to the DE is
Cos9x - cos5x = -2sin2x.sin7x
sin17x - sin3x = 2sin7x.cos10x
so f(x) =
=
Its because the power of zero is undefined
The formula for geometric mean is nth root of the product of all terms. n denotes the number of data. Since you have only two points, 99 and 11, n = 2. The product of both terms is 99 × 11 = 1089. The square root of 1089 is 33. Thus, the answer is 33.
A number can replaced with a variable like x
(X+3)4=16
4x+12=16
4x=4
X=1
(X/4)+3=24
X/4=21
X=84