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Find a cubic polynomial with the sum, sum of the product of its zeros taken two at a time, and the product of its zeros as 3, -1, -3 respectively.

Answer
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Hint: To solve this problem, one should have theoretical knowledge of cubic equations and the relationship between their coefficients and roots. The formulas that will be used to verify this relationship are-α+β+γ=ba, αβ+γβ+γα=ca and αβγ=da. So, using the information given in the question and these three formulas, we will first reform the cubic equation and then we will obtain the equation of the cubic polynomial.

Complete step by step solution:
Let the equation be ax3+bx2+cx+d=0
We will divide both sides by a in the above equation, and then apply the formula for the relationship between the roots and the coefficients, which is given by
α+β+γ=ba, αβ+γβ+γα=ca and αβγ=da.
As it is given that the sum, sum of the product of its zeros taken two at a time, and the product of its zeros as 3, -1, -3 which means
α+β+γ=3, αβ+γβ+γα=1 and αβγ=3.
So, here, we can see that we can substitute these formulas in the equation-
x3+bax2+cax+da=0
x3(α+β+γ)x2+(αβ+γβ+γα)xαβγ=0 
We put the given values to get
x3(3)x2+(1)x+(3)=0 
On simplifying, we get
x33x2x+3=0
Thus, the required cubic polynomial with sum, sum of the product of its zeros taken two at a time, and the product of its zeros 3, -1 and -3 respectively is equals to x33x2x+3=0.

Note: Always remember that general equation of cubic polynomial is ax3+bx2+cx+d=0, where a, b, c and d belongs to set of real numbers and also keep the logic remember that number of roots of polynomial is equals to highest power of x in polynomial. The most common mistake here is that students often forget the negative sign in the sum and the product of roots formula. Try not to make any calculation errors while solving the question.