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If alpha+beta=pi/2, then the maximum val...

If `alpha+beta=pi/2`, then the maximum value of `cosalpha cos beta` is:

A

0

B

1

C

`1/2`

D

`1/4`

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JBD PUBLICATION-MODEL PAPER (10)-EXERCISE
  1. The number of non-empty subsets of the set {1, 2, 3, 4) is

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  2. If f(x)=(2^x+2^-x)/2, then f(x+y) f(x-y) is equal to:

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  3. If alpha+beta=pi/2, then the maximum value of cosalpha cos beta is:

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  4. The amplitude of 1/i is equal to:

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  5. The value of 10C3 is:

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  6. The sum of first 30 natural numbers is:

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  7. The distance between the points A(a cos theta, a sin theta) and B(a co...

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  8. The general equation ax^2+2hxy+by^2+2gx+2fy+c=0 represents a circle if...

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  9. The value of underset(xrarr0)lim (sin2x)/(sin3x) is:

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  10. Two dice are thrown together, the probability that at least one will s...

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  11. If sinx=-5/13 and x lies in IIIrd quadrant. Find the value of secx+tan...

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  12. Prove that: 2 sin^2(3pi)/4+2cos^2pi/4+2s e c^2pi/3=10

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  13. If x+iy=(a+ib)/(a-ib), then prove that x^2+y^2=1

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  14. Find (a+b)^4-(a-b)^4. Hence evaluate : (sqrt3 +sqrt2)^4 -(sqrt3 -sqrt...

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  15. Find the rth term from the end in the expansion of (x+a)^n.

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  16. Show that the points A(2,3,4), B(3,4,2), C(4,2,3) form the vertices o...

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  17. Identify the quantifier in the following statements and write the nega...

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  18. Find the component statements of the following and check whether it is...

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  19. Let A, B, and C be the sets such that A uu B = A uu C and A nn B = A n...

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  20. If f (x) = loge ((1+x)/(1-x)), prove that: f (x) +f (y)= f ((x+y)/(1+x...

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