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A GP has common ratio 3, last term 486, ...

A GP has common ratio 3, last term 486, if the sum of its terms is 728, find its first term.

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CENGAGE PUBLICATION-BINOMIAL THEOREM-All Questions
  1. The last two digits of the number 3^(400) are: (A) 81 (B) 43 (C) ...

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  2. The expression (sqrt(2x^2+1)+sqrt(2x^2-1))^6 + (2/(sqrt(2x^2+1)+sqrt(2...

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  3. A GP has common ratio 3, last term 486, if the sum of its terms is 728...

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  4. If (1+2x+3x^2)^(10)=a0+a1x+a2x^2+.....+a(20)x^(20),t h e na1 equals a....

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  5. Find the number of integral terms in the expansion of (5^(1/2)+7^(1/8)...

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  6. For which of the following values of x ,5t h term is the numerically g...

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  7. For natural numbers m ,n ,if(1-y)^m(1+y)^n=1+a1y+a2y^2+... , and a1=a2...

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  8. If the middle term in the expansion of (x/2+2)^8 is 1120, then find t...

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  9. If (1+x)^n=C0+C1x+C2x^2+...+Cn x^n , t h e n C0-(C0+C1)+(C0+C1+C2)-(C0...

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  10. In the expansion of (x^(2) + 1 + (1)/(x^(2)))^(n), n in N,

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  11. The value of .^(n)C(1)+.^(n+1)C(2)+.^(n+2)C(3)+"….."+.^(n+m-1)C(m) is ...

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  12. If (1+x)^n=C0+C1x+C2 x^2+...+Cn x^n , n in N ,then C0-C1+C2-.....+(-1...

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  13. The 10th term of (3-sqrt((17)/4+3sqrt(2)))^(20) is (a) a irrational nu...

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  14. Find the geometric mean between2a and 8a^3

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  15. Let (1+x^(2))^(2) (1+x)^(n) = underset(k = 0)overset(n+4)suma(k)x^(k)....

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  16. The middle term in the expansion of (x/2+2)^8 is 1120, then x in R is...

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  17. The sum of three numbers of GP is 39/10 and their product is 1. Find...

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  18. The first two term of a G.P are 125, and 25 respectively. Find the 5t...

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  19. If underset(r=0)overset(n)sum((r+2)/(r+1)).^(n)C(r)=(2^(8)-1)/(6). the...

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  20. Let f(x) = a(0) + a(1)x + a(2)x^(2) + "…." + a(n)x^(n) + "…." abd (f(x...

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