Question

Find a quadratic polynomial the sum and product of whose zeros are - 3 and 2 respectively

Answer 1

HEY MATE !!!

let the zeroes be

$\alpha \: and \: \beta$

since,

$\alpha + \beta = \frac{ - b}{a} = \frac{ - 3}{1}$

---- (1)

$\alpha \times \beta = \frac{c}{a} = \frac{2}{1}$

----(2)

from (1) and (2)

$b = 3 \\ a = 1 \\ c = 2$

comparing with the general quadratic equation

${a}^{2} + bx + c = 0$

the required quadratic equation is

${x}^{2} + 3x + 2 = 0$

this question can also be solved using the formula but the way in which I solved is also correct and given the same amount of marks

(it's based on logic so easy to understand)

HOPE YOU'VE FOUND IT IMFORMATIVE !!!

Answer 2

$\alpha + \beta = - 3 \\ \alpha \beta = 2 \\ formula \\ x { }^{2} - ( \alpha + \beta )x + \alpha \beta \\ x {}^{2} - ( - 3) x+ 2 \\ x {}^{2} - + 3x + 2 = 0$