Question

construct a quadratic polynomial whose zero are 1 and -3

Answer 1

x2 - (a+b)x + ab
here a = 1. b= -3
x2 - (-2x) - 3
x2 + 2x - 3

Answer 2

hello users ...

we have given that 
 zeroes of quadratic equation are 1 and -3 

solution :-
let α and β are the roots( zeroes) of equation 
here 
α= 1 and β = -3 

we know that 
sum of roots ( α + β) = - $\frac{coefficient of x }{coefficient of x^{2} }$
and
product of roots (αβ) = $\frac{constant term }{coefficient of x^{2} }$


now
the sum of roots
=> 1+ (-3) = $\frac{-b}{a}$
=>  -2/1 =$\frac{-b}{a}$

and 
product of roots 
=> 1×(-3) =$\frac{c}{a}$ = -3/1

now by comparing 
here a= 1 , b = 2 and c= -3

now
the quadratic equation 
= ax² + bx + c = 0 

putting values, we get

= x² + 2x +(-3) = 0 

=> quadratic equation is x² + 2x -3 = 0 answer 

✮✮hope it helps ✮✮