Question # 1

The solution set of the equation tan^-1x - cot^-1x = cos^-1(2 - x) is

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[0, 1]

[-1, 1]

[1, 3]

None of these

The key for opening a door is in a bunch of 10 keys. A man attempts to open the door by trying the keys at random discarding the wrong key. The probability that the door is opened in the 5th trial is

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1 / 10

2 / 10

3 / 10

4 / 10

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1.5

1.2

8

None of these

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5 / 12

3 / 8

5 / 8

7 / 4

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2

1

5

0

(n + 2) (n + 1) n= ______

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If sin 6θ+ sin 4θ+ sin 2θ, thenθ=

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a^xIn a + c

a^x+ c

x a^x+ c

f (x) = | x | is a/an

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Injective function

Bijective function

Surjective function

Implicit function

If a₁, r and a_nare the first term, common ratio and the nth term respectively of a G. P. then a_n=

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a₁rⁿ

a₁r^n-1

a₁rⁿ⁺¹

a₁r

Only one of the root of ax2 + bx + c =0, a≠ 0 is zero if

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c = 0

c = 0,b≠ 0

b = 0,c = 0

b = 0,c≠ 0

A person standing on the bank of a river observes that the angle subtended by a tree of the opposite bank is 60°, when he retreats 40 m from the bank, he finds the angle to be 30°. The height of the tree and the breadth of the river are