In an arithmetic series the 20th term is 14 and the 40th term is -6. Find the 10th term. How do I do this?
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Originally Posted by Viral In an arithmetic series the 20th term is 14 and the 40th term is -6. Find the 10th term. How do I do this? Where is the nth term is the first term is the number of terms is the common difference. (eq1) (eq2) Solve simultaneously. It would be easiest to eliminate a first
Yeah, I've done that, and got . However, when I do: But the answer is supposed to be 24 >< .
Originally Posted by Viral Yeah, I've done that, and got . However, when I do: But the answer is supposed to be 24 >< . which means I took equation 2 from equation 1:
I'm now told: The first three terms of an arithmetic series are 5x, 20 and 3x. Find the values of x and hence the values of the three terms. What are the steps to do this?
Originally Posted by Viral I'm now told: The first three terms of an arithmetic series are 5x, 20 and 3x. Find the values of x and hence the values of the three terms. What are the steps to do this? By definition: You can then solve U_2 and U_3 simultaneously. Eliminate d since we don't need to find it I get and so , and
Ok, this one is worded really weirdly >< . For this can you just tell me what it's asking, and I'll go from there. For which values of x would the expression form the first three terms of an arithmetic series.
Originally Posted by Viral Ok, this one is worded really weirdly >< . For this can you just tell me what it's asking, and I'll go from there. For which values of x would the expression form the first three terms of an arithmetic series. Do you get what I did above with the first three terms? In this case set the numbers you're given here
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