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AP's question PURE1

https://gyazo.com/135d140bd0b6380ccea5a2cf4c6214c5

Help with part one of question please
Original post by Jian17
https://gyazo.com/135d140bd0b6380ccea5a2cf4c6214c5

Help with part one of question please


You are told a = - 2222 and d = 17

What's the formula for the nth term of an AP?

Once you have that then make an equation as we want nth term > 0
Same thing ine just a bit neater/ nicer

if you know that -2222 if term one and difference is 17 i.e. next term is -2205 etc. You know 100 terms on is +1700 basically fudge the way by doing -2222/17 to work out how many 17s add to get close to 0 .

2) Formula : nth term =a + d(n-1)
U need when goes over 0
So solve by 0>a+d(n-1)
0> -2222+17(n-1)
Then that should give u no terms when is 0. Next whole
Number of N (I assume answer will be decimal) is term which exceeds formula.
Plug that N back into the formula or just add 17 that many times.
Reply 3
Thanks for both answers, i managed to do the question!!
Original post by Canary84
Same thing ine just a bit neater/ nicer

.


MY post was following the rules to just give hints ...

Please - not as much detail next time you help someone in the maths forum. Please read the rules :smile:

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