Category Archives: IIT JEE

$\frac {dy}{dx} + 2y tan x = sin x $

$y (\frac {\pi}{3})=0$

${y_{\max }} = ?$

If y = y(x) is the solution to the differential equation, $\frac {dy}{dx} + 2y tan x = sin x $, $y (\frac {\pi}{3})=0$, then the maximum value of the function y(x) over R is equal to:

(A) $\frac {1}{2} $
(B) $\frac {1}{8} $
(C) $-\frac {15}{4}$
(D) 8 Continue reading $\frac {dy}{dx} + 2y tan x = sin x $

$y (\frac {\pi}{3})=0$

${y_{\max }} = ?$

If for a > 0, the feet of perpendiculars from the points ….

If for a > 0, the feet of perpendiculars from the points A (a, -2a, 3) and B (0, 4, 5) on the plane lx + my + nz = 0 are points C (0, -a, -1) and D respectively, then the length of line segment CD is equal to:

(A) $\sqrt {41} $
(B) $\sqrt {31} $
(C) $\sqrt {66} $
(D) $\sqrt {55} $ Continue reading If for a > 0, the feet of perpendiculars from the points ….

$\omega = z\bar z – 2z + 2$

$\left| {\frac{{z + i}}{{z – 3i}}} \right| = 1$

$Re(\omega ) $=min.

$n_{min.} \in N =?$

$\omega ^n \in R$

Let z and $\omega $ be two complex numbers such that $\omega  = z\bar z – 2z + 2$, $\left| {\frac{{z + i}}{{z – 3i}}} \right| = 1$ and $Re(\omega )$ has minimum value. Then, the minimum value of $n \in N $ for which $\omega ^n $ is real, is equal to _ _ _ _ . Continue reading $\omega = z\bar z – 2z + 2$

$\left| {\frac{{z + i}}{{z – 3i}}} \right| = 1$

$Re(\omega ) $=min.

$n_{min.} \in N =?$

$\omega ^n \in R$

$AB_2 $ is 10% dissociated in water to $A^{2+}$ and $B^-$ ….

$AB_2 $ is 10% dissociated in water to $A^{2+}$ and $B^-$. The boiling point of a 10.0 molal aqueous solution of $AB_2 $ is _ _ _ _ $^ \circ C $. (Round off to the nearest integer)

[Given: Molal elevation constant of water $K_b  = 0.5 K.Kg.mol^{-1} $, boiling point of pure water = $100 ^\circ C $] Continue reading $AB_2 $ is 10% dissociated in water to $A^{2+}$ and $B^-$ ….

The decomposition of formic acid on gold surface follows ….

The decomposition of formic acid on gold surface follows first order kinetics. If the rate constant at 300 K is $1.0 \times 10^{-3} s^{-1} $ and the activation energy $E_a = 11.488 kJ.mol^{-1} $, the rate constant at 200 K is _ _ _ _ $\times 10^{-5} s^{-1} $. (Round off to the nearest integer)

[Given $R = 8.314 J mol^{-1} K^{-1} $] Continue reading The decomposition of formic acid on gold surface follows ….