The number of solutions of the equation
\cos \left( {x + {\pi \over 3}} \right)\cos \left( {{\pi \over 3} - x} \right) = {1 \over 4}{\cos ^2}2x, x∈[−3π,3π] is :
The number of elements in the set S={x∈R:2cos(6x2+x)=4x+4−x} is :
Mathematicspermutations-and-combinations2022hard
The number of ways to distribute 30 identical candies among four children C1, C2, C3 and C4 so that C2 receives at least 4 and at most 7 candies, C3 receives at least 2 and at most 6 candies, is equal to :
Let f(x) be a quadratic polynomial such that f(−2) + f(3) = 0. If one of the roots of f(x) = 0 is −1, then the sum of the roots of f(x) = 0 is equal to :
Let a, b ∈ R be such that the equation ax2−2bx+15=0 has a repeated root α. If α and β are the roots of the equation x2−2bx+21=0, then α2+β2 is equal to :
Let S be the set of all integral values of α for which the sum of squares of two real roots of the quadratic equation 3x2+(α−6)x+(α+3)=0 is minimum. Then S :