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Help with changing degrees into radians?

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1. Attachment 525251525253
I tried changing my calculator to radians and degrees and I thought to change degrees into radians you would have to divide the degrees by pi/180
Anyone help me here?

Question (a) is not the one to be answered
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2. you would multiply degrees by pi/180 to get it to radians if I'm correct
3. (Original post by smooo)
you would multiply degrees by pi/180 to get it to radians if I'm correct
yeah thats right, i just forgot to get the inverse of the angle before changing to radians, thanks!!
4. (Original post by jessnoch)
yeah thats right, i just forgot to get the inverse of the angle before changing to radians, thanks!!
Do you actually need to do it manually though? You can just set your calculator to radians, that way you don't need to convert it from degrees because you'll have the answer in the correct unit straight away. Bear in mind, I am asking. If the question wants you to convert the units then of course do that.
5. (Original post by jessnoch)
yeah thats right, i just forgot to get the inverse of the angle before changing to radians, thanks!!
np, checked over the workings and it seems to be all right
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Do you actually need to do it manually though? You can just set your calculator to radians, that way you don't need to convert it from degrees because you'll have the answer in the correct unit straight away. Bear in mind, I am asking. If the question wants you to convert the units then of course do that.
yeah the question asked to convert the angle into radians on part b, sorry i didn't show that in the question
7. 360 degrees is 2pi radians, 180 degrees is pi radians. Just keep that in mind and things will make sense.
8. (Original post by jessnoch)
yeah the question asked to convert the angle into radians on part b, sorry i didn't show that in the question
Did it actually? I find that highly unlikely. If it said "find the angle in radians" then it means that you can (and should) set your calculator to radian mode and then do cos^(-1) 7/25 and get your answer in radians right away.
9. (Original post by Zacken)
Did it actually? I find that highly unlikely. If it said "find the angle in radians" then it means that you can (and should) set your calculator to radian mode and then do cos^(-1) 7/25 and get your answer in radians right away.
Question (a) asked to show that the angle was 7/25 and then question (b) asked to find the angle in radians, so I did cos-1(7/25) and then did pi/180. I had my calculator set to degrees so I didn't get the direct answer, but I still got the right answer, so either way is fine I think.
10. (Original post by jessnoch)
Question (a) asked to show that the angle was 7/25 and then question (b) asked to find the angle in radians, so I did cos-1(7/25) and then did pi/180. I had my calculator set to degrees so I didn't get the direct answer, but I still got the right answer, so either way is fine I think.
Yes, either way is fine. But that's just... well. Why on earth would you do that? You're just setting yourself up for silly mistakes. Set your calculator in radian mode, you're at A-Level and radians is by far the most prevalent unit you will use. Might as well start getting used to it now.
11. (Original post by Zacken)
Yes, either way is fine. But that's just... well. Why on earth would you do that? You're just setting yourself up for silly mistakes. Set your calculator in radian mode, you're at A-Level and radians is by far the most prevalent unit you will use. Might as well start getting used to it now.
I was confused on the question so I tried doing the answer in radian and degrees mode, and when I realised what to actually do i was already set in degrees. I do usually always have my calculator set to radian mode when doing these styled questions.

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