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Why bother with a post grad course - waste of time? 17-10-2016
1. I've been staring at this question for hours. My mind is broken. Its only a 3 marker but I cant seem to rearrange the equation and get the same answer as the markscheme. I think I'm on the verge of a breakdown because I swear I've done this question (with ease) before!

Anyhow: x=Asin(wt+e), rearrange for t.

x=0.4
A=0.8
w=5.24
e= pi/2

t should = (-)0.201 ...but I cant seem to get that answer
2. (Original post by donte)
I've been staring at this question for hours. My mind is broken. Its only a 3 marker but I cant seem to rearrange the equation and get the same answer as the markscheme. I think I'm on the verge of a breakdown because I swear I've done this question (with ease) before!

Anyhow: x=Asin(wt+e), rearrange for t.

x=0.4
A=0.8
w=5.24
e= pi/2

t should = (-)0.201 ...but I cant seem to get that answer
I got 5.43 when i did it. After that I thought maybe I would try the wave function formula but that didn't work out either. Maybe the marking schemes wrong, a few past papers I've done the marking scheme has been blatantly wrong.

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3. (Original post by donte)
I've been staring at this question for hours. My mind is broken. Its only a 3 marker but I cant seem to rearrange the equation and get the same answer as the markscheme. I think I'm on the verge of a breakdown because I swear I've done this question (with ease) before!

Anyhow: x=Asin(wt+e), rearrange for t.

x=0.4
A=0.8
w=5.24
e= pi/2

t should = (-)0.201 ...but I cant seem to get that answer
Im assuming this is probably an extension of a previous question, assuming you're getting an answer close to their answer probably due to rounding somewhere
4. (Original post by samb1234)
Im assuming this is probably an extension of a previous question, assuming you're getting an answer close to their answer probably due to rounding somewhere
I was originally using 5.24, the markscheme uses 5.2. I used 5.2 as well and it hasnt made a difference really
5. (Original post by RossB1702)
I got 5.43 when i did it. After that I thought maybe I would try the wave function formula but that didn't work out either. Maybe the marking schemes wrong, a few past papers I've done the marking scheme has been blatantly wrong.

Posted from TSR Mobile
Subbed 5.2 in for t and got the correct answer for x to 3 sig figs, so the ms cant be wrong. I feel like I've rearranged it wrong but I've tried rearranging it so many different ways and I'm still no closer to it.
6. (Original post by donte)
Subbed 5.2 in for t and got the correct answer for x to 3 sig figs, so the ms cant be wrong. I feel like I've rearranged it wrong but I've tried rearranging it so many different ways and I'm still no closer to it.
I don't understand how t is -0.201.

Posted from TSR Mobile
7. (Original post by donte)
I was originally using 5.24, the markscheme uses 5.2. I used 5.2 as well and it hasnt made a difference really
Using 5.2 gives the answer they have. Sin(x+pi/2) = cos(x)

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