What's the difference between sin^2(x) and sin(x^2)?

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Homework Statement



what's the difference between sin^2(x) and sin(x^2)?


Homework Equations





The Attempt at a Solution



I can't do sin^2(x) on the calculator. let's just use sin(25) as an example, what's the difference?
 
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[itex]sin^{2}x = sinxsinx[/itex]
The other 1 is just squaring the x not the whole function.Also on a side note,
[itex]sinx+sinx = 2sinx[/itex]
 
bobsmith76 said:

Homework Statement



what's the difference between sin^2(x) and sin(x^2)?

The Attempt at a Solution



I can't do sin^2(x) on the calculator. let's just use sin(25) as an example, what's the difference?
Indeed. if x = 5, sin2(x) ≈ 0.919536, whereas sin(x2) ≈ -0.132352
 
sin2x MEANS (sin x)2.

Which you can calculate on your calculator.

IMHO you are not the only one and not totally at fault to be confused - sin2x as far as I can see is a sort of mathematical slang, not strictly logical (so no wonder your calculator doesn't understand it either) which by its antiquity is let through and is universal - so there it is to get used to.