1.

Find the quadratic polynomial whose zeroes are -3 and 3​

Answer»

\large\underline{\sf{Given- }}

The zeroes of the quadratic polynomial as - 3 and 3.

\large\underline{\sf{To\:Find - }}

The quadratic polynomial

\large\underline{\sf{Solution-}}

Given that

- 3 and 3 are the zeroes of quadratic polynomial.

So,

\rm :\longmapsto\:Let \:  \alpha   \:  =  \:  -  \: 3 \:  \: and \:  \: \beta  \:  =  \: 3

Now,

\rm :\longmapsto\:Sum \: of \: zeroes =  \alpha +  \beta  =  - 3 + 3 = 0

and

\rm :\longmapsto\:Product \: of \: zeroes =  \alpha  \beta  =  - 3 \times 3 =  - 9

We KNOW,

\sf \: If \:  \alpha \: and \:   \beta   \: are \:  the \: zeroes \: of \: quadratic \: polynomial \: then

\sf \: the \: <klux>REQUIRED</klux> \: polynomial \: f(x) \: is \:

\rm :\longmapsto\: \sf \: f(x) \:  = k\bigg(  {x}^{2} - ( \alpha  +  \beta )x +  \alpha  \beta  \bigg)  \: where \: k  \ne \: 0

Thus,

The required Quadratic polynomial whose zeroes are- 3 and 3 is

\rm :\longmapsto\: \sf \: f(x) = k\bigg(  {x}^{2} - 0x - 9 \bigg)  \: where \: k \ne0

\rm :\longmapsto\:\sf \: f(x) = k\bigg(  {x}^{2}  - 9 \bigg)  \: where \: k \ne0

ADDITIONAL Information :-

\sf \: If  \:  \alpha  \: and \:  \beta  \: are \:  the \: zeroes \: of \: f(x) = a {x}^{2}  + bx + c \: then

\boxed{{\sf Sum\ of\ the\ zeroes=\frac{-coefficient\ of\ x}{coefficient\ of\ x^{2}}}}

Or

\boxed{{\tt Sum\ of\ the\ zeroes=\frac{-b}{a}}}

And

\boxed{{\sf Sum\ of\ the\ zeroes=\frac{-coefficient\ of\ x}{coefficient\ of\ x^{2}}}}

Or

\boxed{{\sf Product\ of\ the\ zeroes=\frac{Constant}{coefficient\ of\ x^{2}}}}

\boxed{ \sf{  \:  { \alpha }^{2}  +  { \beta }^{2}  =  {( \alpha +   \beta) }^{2}  - 2 \alpha  \beta }}

\boxed{ \sf{  \:  { \alpha }^{3}  +  { \beta }^{3}  =  {( \alpha +   \beta) }^{3}  - 3 \alpha  \beta( \alpha  +  \beta ) }}



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