I'm so confused with trig...

Why is the graph of sin(theta) different from the graph of sin(x)?

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- Aug 5th 2011, 06:49 AMexplodingtoenailsDifference between theta and x?
I'm so confused with trig...

Why is the graph of sin(theta) different from the graph of sin(x)? - Aug 5th 2011, 06:59 AMPlatoRe: Difference between theta and x?
- Aug 5th 2011, 07:02 AMOpalgRe: Difference between theta and x?
It isn't different, provided that $\displaystyle \theta$ and $\displaystyle x$ are measured in the same units. But if $\displaystyle \theta$ is measured in radians and $\displaystyle x$ is measured in degrees (say), then the scale of the horzontal axis will be different.

- Aug 5th 2011, 09:03 AMTheChazRe: Difference between theta and x?
- Aug 5th 2011, 10:33 AMHallsofIvyRe: Difference between theta and x?
Another point "x" and "y" are typically used in a rectangular coordinate system and "r" and "$\displaystyle \theta$" are used in polar coordinates. You can, of course, use whatever letters you wish.

The graph of "y= sin(x)", in**rectangular coordinates**is the "sine wave".

The graph of "$\displaystyle r= sin(\theta)$", in**polar coordinates**is the circle with center at (0, 1/2) and radius 1/2, as $\displaystyle \theta$ goes from 0 to $\displaystyle \pi$.

But, again, the difference is because of the coordinate systems, not what the variables are called. - Aug 5th 2011, 12:39 PMexplodingtoenailsRe: Difference between theta and x?
Ahh I see. Thanks guys!!!