For this case we have the following equation:
r = 9 sin (θ)
In addition, we have the following change of variables:
y = r * sine (θ)
Rewriting the equation we have:
r = 9 sin (θ)
r = 9 (y / r)
r ^ 2 = 9y
On the other hand:
r ^ 2 = x ^ 2 + y ^ 2
Substituting values:
x ^ 2 + y ^ 2 = 9y
Rewriting:
x ^ 2 + y ^ 2 - 9y = 0
Completing squares:
x ^ 2 + y ^ 2 - 9y + (-9/2) ^ 2 = (-9/2) ^ 2
Rewriting:
x ^ 2 + 1/4 (2y-9) ^ 2 = 81/4
4x ^ 2 + (2y-9) ^ 2 = 81
Answer:
The Cartesian equation is:
4x ^ 2 + (2y-9) ^ 2 = 81
Answer:
Step-by-step explanation:
To find the inverse function, solve for y:
![x=f(y)\\\\x=4y^4\\\\\dfrac{x}{4}=y^4\\\\\pm\sqrt[4]{\dfrac{x}{4}}=y\\\\f^{-1}(x)=\pm\sqrt[4]{\dfrac{x}{4}}](https://tex.z-dn.net/?f=x%3Df%28y%29%5C%5C%5C%5Cx%3D4y%5E4%5C%5C%5C%5C%5Cdfrac%7Bx%7D%7B4%7D%3Dy%5E4%5C%5C%5C%5C%5Cpm%5Csqrt%5B4%5D%7B%5Cdfrac%7Bx%7D%7B4%7D%7D%3Dy%5C%5C%5C%5Cf%5E%7B-1%7D%28x%29%3D%5Cpm%5Csqrt%5B4%5D%7B%5Cdfrac%7Bx%7D%7B4%7D%7D)
f(x) is an even function, so f(-x) = f(x). Then the inverse relation is double-valued: for any given y, there can be either of two x-values that will give that result.
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A function is single-valued. That means any given domain value maps to exactly one range value. The test of this is the "vertical line test." If a vertical line intersects the graph in more than one point, then that x-value maps to more than one y-value.
The horizontal line test is similar. It is used to determine whether a function has an inverse function. If a horizontal line intersects the graph in more than one place, the inverse relation is not a function.
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Since the inverse relation for the given f(x) maps every x to two y-values, it is not a function. You can also tell this by the fact that f(x) is an even function, so does not pass the horizontal line test. When f(x) doesn't pass the horizontal line test, f^-1(x) cannot pass the vertical line test.
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The attached graph shows the inverse relation (called f₁(x)). It also shows a vertical line intersecting that graph in more than one place.
If i did the math correctly one number is 50
19 has two factors: 1, 19
21 has four factors: 1, 3, 7, 21
23 has two factors: 1, 23
And we need a number that has more than four factors and is greater than 25.
Factors of 50- 1, 2, 5, 10, 25, 50
50has six factors and is greater than 25.
2 2/3 = 2x3+2/3 = 8/3
8/3 / 1/3 = 8/3 x 3/1 = 8/1 = 8