## Monday, December 28, 2009

### IIT JEE Mathematics Final Revision Problem Set 12

1. lim h→0 [ln(1+2h)-2 ln(1+h)]/h² = ______________________.

2. An ellipse has OB as a semi-minor axis. F,F' are its foci, and the angle FBF' is a right angle. Then the eccentricity of the elliplse if _______________ .

3. If cos (x-y), cos x and cos (x+y) are in HP, then cos x sec (y/2) = _____________________.

4. Let x be the arithmetic mean and y, z be the two geometric means between any two positive numbers.
Then (y3+z³)/xyz + __________________ .

5.Consider the following statements S and R.

S: Both sin x and cos x are decreasing functions in the interval (π/2, π)
R: If a differentiable function decreases in an interval (a,b), then its derivative also decreases in (a,b).

Which of the folowing is true.

a. Both S and R are correct, but R is not a correct explanation for S.
b. Both S and R are wrong.
c. S is correct and R is the correct explanation for S.
d. S is correct and R is wrong.

Questions 1 to 4 are from cancelled paper 1997 JEE
Questions 5 is from IIT JEE 2000