How to solve this?

I CAN solve it but I need shortcut.

The solution button isn't working in the practise section.

#Algebra #MATHS #A #E

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`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
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Comments

Hey Aryan! Nice question by the way..This question is related to Arithmetic Progression(A.P.)...although i am not sure if you know about them...you can see that every second term has a difference of 14...like the second term is -14 and the fourth term is 0, and similarly, the sixth term is +14...So the numbers at the even place form and A.P. with the first term (a) as -14 and the common difference (d) as +14...Since we are looking at the even places the number of term we need to find is not the 60th but the 30th term. So the number of term we need to find (n) is 30. Therefore, using the formula for finding the n'th term...

n'th term = a + (n-1) d

              = -14 + (30-1) 14



             = -14 + 29 x 14



            = -14 + 406



           = 392 should be your answer

A Former Brilliant Member - 7 years, 3 months ago

I guess so. First I thought that its just repetition of terms by change of signs. I will try it out and let you know.

Aryan Gaikwad - 7 years, 3 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$