Subject

Mathematics

Class

JEE Class 12

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsMultiple Choice Questions

11.

If H is the harmonic mean between P and Q, then the value of HP + HQ is

  • 2

  • PQP +Q

  • 12

  • P +QPQ


12.

If cosx + cos2x = 1, then the value of sin12x + 3sin10x + 3sin8x + sin6x - 1, is equal to :

  • 2

  • 1

  • - 1

  • 0


13.

The product of all values of cosα + isinα3/5 is :

  • 1

  • cosα + isinα

  • cos3α + isin3α

  • cos5α + isin5α


14.

The imaginary part of 1 +i2i2i - 1 is :

  • 45

  • 0

  • 25

  • - 45


Advertisement
15.

The equation of a directrix of the ellipse x216 + y225 = 1 is :

  • 3y = 5

  • y = 5

  • 3y = 25

  • y = 3


16.

If the normal at (ap, 2ap) on the parabola y2 = 4ax, meets the parabola again at (aq2 , 2aq), then

  • p2 + pq + 2 = 0

  • p2 - pq + 2 = 0

  • q2 + pq + 2 = 0

  • p2 + pq + 1


17.

The length of the straight line x - 3y = 1 intercepted by the hyperbola x2 - 4y2 = 1 is :

  • 10

  • 65

  • 110

  • 6510


18.

The curve described parametrically by x = t2 + 2t - 1, y = 3t + 5 represents :

  • an ellipse

  • a hyperbola

  • a parabola

  • a circle


Advertisement
19.

The function f (x) = x2 e- 2x, x > 0. Then the maximum value of f (x) is :

  • 1e

  • 12e

  • 1e2

  • 4e4


Advertisement

20.

If (x + y)sinu = x2y2, then xux + yuy is equal to

  • 1e

  • 12e

  • 1e2

  • 4e4


D.

4e4

x + ysinu = x2y2       ...(i)
On differentiating partially w.r.t. x of Eq. (i),

we get

1 + 0sinu + x + ycosuux = 2xy2 xsinu + x2 + xycosuux = 2x2y2       ...(ii)On differentiating partially w.r.t. y of Eq. (i), we get0 + 1sinu + x + ycosuuy =  2x2y  ysinu + xy + y2cosuuy =  2x2y2      ...(iii)On adding Eqs. (ii) and (iii), we getx + ysinu + x + yxux + yuycosu = 4x2y2       x2y2 + x + yxux + yuycosu = 4x2y2                    x + yxux + yuycosu = 3x2y2                    x + yxux + yuycosu = 3x + ysinu

        xux + yuy = 3tanu


Advertisement
Advertisement