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# I need help. C4 watch

1. See attached image.

King regards
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2. .
3. (Original post by hajs)
.
Arithmetic slip somewhere

CA=(-3,-6,-3)

CB=(-10,0,-4)

Giving 42/sqrt(116x54)
4. (Original post by ghostwalker)
Arithmetic slip somewhere

CA=(-3,-6,-3)

CB=(-10,0,-4)

Giving 42/sqrt(116x54)
Oh! Wait, so do you get that from doing (A)-(C) ?
5. (Original post by hajs)
Oh! Wait, so do you get that from doing (A)-(C) ?
To get CA, yes.
6. (Original post by ghostwalker)
To get CA, yes.
Omg ahahha I realised what I did now! Thank you!!!

7. Isnt is 1/lambda sin(lambdaT)
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8. (Original post by hajs)

Isnt is 1/lambda sin(lambdaT)
if you can differentiate the second line to get the first line then it is good.
9. (Original post by the bear)
if you can differentiate the second line to get the first line then it is good.
How would i do it without knowing the second line?
10. (Original post by hajs)

Isnt is 1/lambda sin(lambdaT)
Lamba is a constant.
If you place it outside the integral then yes you are correct you get 1/lambda sin(lambdaT). But when you multiply back in the lambda that you placed outside the integral then they cancel so you are left with line 2.
11. (Original post by LouN1997)
Lamba is a constant.
If you place it outside the integral then yes you are correct you get 1/lambda sin(lambdaT). But when you multiply back in the lambda that you placed outside the integral then they cancel so you are left with line 2.
From where? I didnt place nothing outside..
12. OHHHHH.
13. Hahah Silly me, THANKS!! +Rep.
14. if you have to integrate a fraction:

always check to see if the top is the derivative ( dy/dx ) of the underneath. if so the the answer is ln|underneath| + c

here 1 is the derivative of p ...

on the RHS you could do a substitution: let W = λt

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