The coefficient of xn in expansion of (1+x)(1-x)n is
(n-1)
(-1)n(1-n)
(-1)n-1(n-1)2
(-1)n-1n
B.
(-1)n(1-n)
The coefficient of xn in expansion of (1+x)(1-x)n is = coefficient of xn + coefficient of xn-1
If the cube roots of unity are 1, ω, ω2 then the roots of the equation (x – 1)3 + 8 = 0, are
The value of α for which the sum of the squares of the roots of the equation x2 – (a – 2)x – a – 1 = 0 assume the least value is
If roots of the equation x2 – bx + c = 0 be two consectutive integers, then b2 – 4c equals
If z1 and z2 are two non-zero complex numbers such that |z1 + z2| = |z1| + |z2| then argz1 – argz2 is equal to
If the equation anxn +an-1xn-1 +....... +a1x =0, a1 ≠ 0, n≥2, has a positive root x = α, then the equation nanxn-1 + (n-1)an-1xn-2 +......+a1 = 0 has a positive root, which is
Mock Test Series
