Sketch Curves: y=5x^(3/4), y=-2x^(-3/2)

AI Thread Summary
The discussion focuses on sketching the curves of the equations y=5x^(3/4) and y=-2x^(-3/2). Participants note that these equations do not fit the general forms of conic sections like circles or parabolas. It is suggested to start by determining the domains of the functions and manipulating the fractional exponents for better understanding. Calculating y-values for various x-values and plotting them is recommended to create smooth curves. Overall, the emphasis is on understanding the nature of the functions rather than applying conic section equations.
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Homework Statement


Sketch the curves with the following equations:
a) y=5x^(3/4)
b) y=-2x^(-3/2)

Homework Equations


The general equation of curves (circles, parabola, ellipse, hyperbola)

The Attempt at a Solution


It seems to me that this question is not exactly a coordinate geometry question. At first, I thought this is a parametric equation, but parametric equation use t instead of y. Then, I thought of substituting x with some other things. But that fails as well. (The fraction power make it not rational to be substituted by x^2, x^3 and so on.) The equation doesn't resemble general equation circles, parabola, ellipse, or hyperbola.

How should I attempt this question? Is equation of curves really useful to solve this question?
 
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You are given two functions y(x). Start with finding their domains.
 
There are other basic graphs of functions, so these would be some of them. Perahps it would be easier for you to re-write the fractional exponents. Well, that would be if you have gotten to that (or know how to).

I will let you know though, both of those equations don't resemble a circle, parabola, ellipse, or hyperbola.

As I said, try manipulating the exponents.
 
As pointed out, these are not quadratic functions and so their graphs are not conic-sections (circle, ellipse, hyperbola, parabola). Basically, just calculate y for a number of x values and draw a smooth curve through the points. As radou said, you'd better check the domains.
 
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