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1. Hi, need some help with part B of my question. I've done part A no problem but can't do B, the way I usually do it by plugging in x=0 isn't working so can someone show me how they done it please! Thanks. I know it should be the easier part of the question but honestly hitting mind blanks with it now, appreciate any help
2. What actually went wrong when you tried x=0?
3. (Original post by bananagrimshaw)

Hi, need some help with part B of my question. I've done part A no problem but can't do B, the way I usually do it by plugging in x=0 isn't working so can someone show me how they done it please! Thanks. I know it should be the easier part of the question but honestly hitting mind blanks with it now, appreciate any help
Plugging in x=0 should work, you get and you can work out the value of cosine there by using a right-angled triangle or a calculator.
4. (Original post by RDKGames)
Plugging in x=0 should work, you get and you can work out the value of cosine there by using a right-angled triangle or a calculator.
I know that pi/6 is 30° and that's root 3 over 2 but then I'm not sure how you get the answer of 4 root 3 or 6.93. I get 7.03 when I try to get a decimal answer and to get 4 root 3 from y= 8cos root 3 over 2, I'm assuming I devide the 8 by 2 but I've never been told that so I'm not sure, how would you do it? Thanks
5. (Original post by bananagrimshaw)
I know that pi/6 is 30° and that's root 3 over 2 but then I'm not sure how you get the answer of 4 root 3 or 6.93. I get 7.03 when I try to get a decimal answer and to get 4 root 3 from y= 8cos root 3 over 2, I'm assuming I devide the 8 by 2 but I've never been told that so I'm not sure, how would you do it? Thanks
Right I have no idea what is going on here with your working if I'm honest with you.

Yes radians is equivalent to degrees. So as you said yourself. Now to get you simply multiply both sides of by 8 which gets you the as required.
6. (Original post by RDKGames)
Right I have no idea what is going on here with your working if I'm honest with you.

Yes radians is equivalent to degrees. So as you said yourself. Now to get you simply multiply both sides of by 8 which gets you the as required.
Okay could you explain the last step, why do you times both sides by 8? I have never been told that and it explains why I've got stuck on this question. I'm sorry for being a pain! Really appreciate the help!!
7. (Original post by bananagrimshaw)
Okay could you explain the last step, why do you times both sides by 8? I have never been told that and it explains why I've got stuck on this question. I'm sorry for being a pain! Really appreciate the help!!
Because then you have on one side and its equivalent numerical value on the other which is what you want.
8. (Original post by RDKGames)
Because then you have on one side and its equivalent numerical value on the other which is what you want.
Okay thank you very much! I'm away to practice ones like this

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