Inactive Tutor answered • 01/11/16
Tutor
New to Wyzant
If the question is (1 + x + x-3)*7, then the term which is independent of x is 7.
If the question is (1 + x + x-3)7 , then the term which is independent of x is 1.
Inactive Tutor
Is the question asking for the constant term after the expansion is performed?
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01/11/16
Inactive Tutor
I assume the question is asking for the constant term because it is only this term is independent of x. In Binomial expansion only the constant term is independent from x other terms would have x in it.
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01/11/16
Daniel K.
The question is asking for the constant term after the expansion is performed. So can u worked it out?
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01/11/16
Inactive Tutor
Expanding (1+x+x-3)*7 = 7 + 7x + 7x-3
Expanding (1+x+x-3)7 is more complicated and has to use Binomial Expansion to do it.
But if our focus is to find the term which does not have x, then we may rewrite the expansion as below:
[1+(x + x-3)]7 = 1 + 7(x + x-3) + 21(x + x-3)2 + 35(x + x-3)3 + 35(x + x-3)4+ 21(x + x-3)5+7(x + x-3)6+(x + x-3)7
Only the first term 1 is independent of x
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01/11/16
Daniel K.
Nope. The answer is 141.
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01/11/16
Daniel K.
01/11/16