The maximum possible value of x^2 + y^2 – 4x – 6y, x, y real, subject to the condition | x + y | + | x – y | = 4
(A) is 12 (B) is 28 (C) is 72 (D) does not exist
Let f(x) = x^12 – x^9 + x^4 – x + 1. Which of the following is true ?
(A) f is one-one
(B) f has a real root
(C) f ′ never vanishes
(D) f takes only positive values
Let A and B be any two n × n matrices such that the following conditions hold : AB = BA and there exist
positive integers k and l such that Ak = I (the identity matrix) and Bl = 0 (the zero matrix). Then-
(A) A + B = I (B) det (AB) = 0
(C) det (A + B) ≠ 0 (D) (A + B)m = 0 for some integer m
The locus of the point P = (a, b) where a, b are real numbers such that the roots of x^3 + ax^2 + bx + a = 0 are in
arithmetic progression is-
(A) an ellipse
(B) a circle
(C) a parabola whose vertex in on the y-axis
(D) a parabola whose vertex is on the x-axis
An electrode is placed in the axioplasm of a mammalian axon and another electrode is placed just outside the
axon. The potential difference measured will be-
(A) 0 (B) –70 mV
(C) –70 μV (D) +70 μV
Soon after the three germ layers are formed in a developing embryo, the process of organogenesis starts. The
human brain is formed from the-
(A) ectoderm
(B) endoderm
(C) mesoderm
(D) partly endoderm and partly mesoderm
Circadian Rhythm is an endogenously driven cycle for biochemical, physiological and behavioral processes.
In humans, the approximate duration of this 'biological clock' is-
(A) 1 Hour (B) 6 Hours (C) 12 Hours (D) 24 Hours