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Let X be a random variable with E(X)=3 and Var(X)=9. Then E(X^2) is? (The answer should be 18 but explain?)? What is the role of hydroxyapatite and collagen in bone structure? How we can integrate Jenkins with selenium WebDriver? Can acceleration and displacement reach maximal values during SHM simultaneously? Explain why.? If f (x)=ax^(2)+bx+c And f (x-1)+f (x)+f (x+1)=x^(2)+1 find f (2)?
I am new to function and I don't know how to solve such questions?