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If (1+2x+x^2)^n=sum(r=0)^(2n)ar x^r ,the...

If `(1+2x+x^2)^n=sum_(r=0)^(2n)a_r x^r` ,then `a_r ` is a.`(.^nC_2)^2` b. `.^n C_r .^n C_(r+1)` c. `.^(2n) C_r` d. `.^(2n) C_(r+1)`

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If (1-x^2)^n=sum_(r=0)^n a_r x^r(1-x)^(2n-r),t h e na_r is equal to ^n C_r b. ^n C_r3^r c. ^2n C_r d. ^n C_r2^r

.^(n)C_(r)+2.^(n)C_(r-1)+.^(n)C_(r-2)=

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If n in N such that is not a multiple of 3 and (1+x+x^(2))^(n) = sum_(r=0)^(2n) a_(r ). X^(r ) , then find the value of sum_(r=0)^(n) (-1)^(r ).a_(r).""^(n)C_(r ) .

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CENGAGE ENGLISH-BINOMIAL THEOREM-All Questions
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  2. If the coefficients of 5th, 6th , and 7th terms in the expansion of (1...

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  3. If (1+2x+x^2)^n=sum(r=0)^(2n)ar x^r ,then ar is a.(.^nC2)^2 b. .^n ...

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  5. If the coefficients of rth and (r+1)t h terms in the expansion of (3+7...

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  10. The expression (x+((x^3-1)^(1/2))/2)^5+""(x-((x^3-1)^(1/2))/2)^5 is a ...

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  11. Find ((dy) /dx) of sin(costheta) is

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  13. Coefficient of x^(11) in the expansion of (1+x^2)^4(1+x^3)^7(1+x^4)^(...

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  15. The coefficient of x^4 in (x//2-3//x^2)^10 is a.(405)/(256) b. (504)/(...

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  17. The sum underset(m)overset(i=0)sum ({:(10),(i):})({:(20),(m-i):}), (wh...

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  18. The coefficient of X^24in the expansion of (1+X^2 )^12(1+X^12)(1+X^24)

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  19. The term independent of a in the expansion of (1+sqrta+ 1/(sqrta-1))^-...

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