In a triangle ABC,if \(cos^{2}A-sin^{2}B+cos^{2}C=0\) ,then the value of \(cosAcosBcosC\) is
For any real number \(x\), the least value of \(4cosx-3sinx+5\) is ?
For four observations X,X2,X3,X4, it is given that ,\(∑x_i^{2}=656\) and \(∑x_i=32\). Then, the variance of these four observations is ?
Let S={\(a,b,c\)} be the sample space with the associated probabilities satisfying \(P(a)=2P(b)\) and \(P(b)=2P(c).\)Then the value of \(P(a)\) is