Question

0a%20_%7B6%7D%20x%20%5E%7B6%7D%20%2B%20a%20_%7B5%7D%20x%20%5E%7B5%7D%2B....%20%5C%5C%20%5Csf%20%2B%20a%E2%82%81x%20%2B%20a%20_%7B0%7D%2C%20then%20%5C%3A%20%5C%3A%20a_0%20%2B%20a%E2%82%81%20%2B%20a%E2%82%82%20%2B%20a_3%20%2B%20a_4%20%2B%20a_5%20%2B%20a_6%20%2B%20a7%20%3D%20" id="TexFormula1" title=" \sf \: If (3x-1) ^{7} = a _{7} x ^{7} + a _{6} x ^{6} + a _{5} x ^{5}+.... \\ \sf + a₁x + a _{0}, then \: \: a_0 + a₁ + a₂ + a_3 + a_4 + a_5 + a_6 + a7 = " alt=" \sf \: If (3x-1) ^{7} = a _{7} x ^{7} + a _{6} x ^{6} + a _{5} x ^{5}+.... \\ \sf + a₁x + a _{0}, then \: \: a_0 + a₁ + a₂ + a_3 + a_4 + a_5 + a_6 + a7 = " align="absmiddle" class="latex-formula">
a)0
b)1
c)128
d)64

Please solve this for me. Need step-by-step explanation. Spam free answer required. Thank you in anticipation.

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Answer 1

Answer is c) 128

I added the step by step process in the pic attached, I don't know how to explain it very well but you can use binomial theorem for (3x-1)^7

Then you can add up all the coefficients of the calculated values as the question mentions afterwards a^7 + a^6 +..... which means it only wants you to add up the coefficients of the consecutive x terms, otherwise it would say a^7x^7 + a^6x^6 +..... and so on

Hope this helps :)

Answer 2

Answer:

hope it helps have a great day

Answer is option C