The value of 2 + 4 + 6 +…….+ 2n is

**A. ** n(n-1)/2

**B. ** n(n+1)/2

**C. ** 2n(2n+1)/2

**D. ** n(n + 1)

**Answer : ****Option D**

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The coefficient of x^{6} in (2 + 2x)^{10}
is

**A. ** ^{10}C_{6}

**B. ** 2^{6}

**C. ** ^{10}C_{6}
2^{6}

**D. ** ^{10}C_{6}^{
}2^{10}

**Answer : ****Option D**

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The coefficient of x^{8}y^{12}
in the expansion of (2x + 3y)^{20} is

**A. ** 0

**B. ** 2^{8}3^{12}

**C. ** 2^{8}3^{12} + 2^{12}3^{8}

**D. ** ^{20}C_{8}
2^{8}3^{12}

**Answer : ****Option D**

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If ^{n}C_{10} > ^{n}C_{r}
for all possible r, then a value of n is

**A. ** 10

**B. ** 21

**C. ** 19

**D. ** 20

**Answer : ****Option D**

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If a is the arithmetic mean and g is the geometric mean of two numbers, then

**A. ** a ≤ g

**B. ** a ≥ g

**C. ** a = g

**D. ** a > g

**Answer : ****Option B**

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If (1 + x^{2})^{2} (1 + x)^{n}
= a_{0} + a_{1}x + a_{2}x^{2} +……..+ x^{n+4}
and if a_{0}, a_{1}, a_{2} are in AP, then n is

**A. ** 1

**B. ** 2

**C. ** 3

**D. ** 4

**Answer : ****Option C**

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If a, 8, b are in AP, a, 4, b are in GP, and if a, x, b are in HP then x is

**A. ** 2

**B. ** 1

**C. ** 4

**D. ** 16

**Answer : ****Option A**

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The sequence , form an

**A. ** AP

**B. ** GP

**C. ** HP

**D. ** AGP

**Answer : ****Option C**

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The HM of two positive numbers whose AM and GM are 16, 8 respectively is

**A. ** 10

**B. ** 6

**C. ** 5

**D. ** 4

**Answer : ****Option D**

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If S_{n} denotes the sum of n
terms of an AP whose common difference is d, the value of S_{n} - 2S_{n}_{-1} + S_{n}_{-2} is

No Explaination.

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