Question

1. Which row of Pascal’s triangle has terms that sum to 648?

2. Find the fourth term of the expansion of (2? − 1) .

Answer 1

D Pascal's triangle are 2 1 3 3 4 6 4 These the efficients of expansion of carb) ie, arb = 1.atlob (a+b)² = lätzabt ih (a+b)? 1.9² + 3a²b+ sab² + 1.6² ale can respresent these terms as 1 Quý vị yvº 21648 23 24 21162 3 3 27 39 3 v on mus ana expansion of n.th power the row of Pascal's triangle is 2 neo no n, n nen ney sum + we . It's ne the an But 648= 2 x 37 can't write 648 as power of 2 only. row of Pascal's triangle has terms that sum to 648 9 th row give sum 512 and 10-th row give sum 1024. , 70

2) The expansion of 2x-1 has only two terms. Therefore we can't find the fourth term in expansion. Please check if there is any power for (2x-1). Please comment if any changes. I will give you answer.