if [tex] \alpha[/tex],[tex] \beta [/tex]are zeroes of the polynomial p(x)=5x²+5x+1 then find the value of[tex] \alpha ^{2} + \beta ^{2} [/tex] About the author Allison
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀☆ GIVEN⠀ POLYNOMIAL – p(x) = 5x² + 5x + 1 : ⠀⠀⠀⠀⠀━━━━━━━━━━━━━━━━━━━⠀ ⠀⠀⠀⠀⠀The Cofficients of Polynomial p(x) = 5x² + 5x + 1 : The Cofficient of x² = 5 The Cofficient of x = 5 Constant term = 1 ⠀⠀⠀⠀⠀━━━━━━━━━━━━━━━━━━━⠀ ⠀⠀⠀⠀ Given that, [tex] \alpha\: \& \:\beta [/tex] are two zeroes of p(x) . As, We know that , [tex]\bf{\underline {\star \: Sum \:of\:zeroes \::}}\\[/tex] [tex]\bf{ \alpha + \beta = \bigg( \dfrac{-(Cofficient \:of\:x^2)}{Cofficient \:of\:x}\bigg) }\\\\[/tex] ⠀⠀⠀⠀⠀⠀[tex]\underline {\frak{\star\:Now \: By \: Substituting \: the \: known \: Cofficients\::}}\\[/tex] ⠀⠀⠀⠀[tex]:\implies\sf { \alpha + \beta = \bigg( \dfrac{-5}{5}\bigg) }\\\\[/tex] ⠀⠀⠀⠀[tex]:\implies\sf { \alpha + \beta = \bigg( \cancel {\dfrac{-5}{5}}\bigg) }\\\\[/tex] ⠀⠀⠀⠀[tex]:\implies\bf { \alpha + \beta = -1 }\\\\[/tex] And, As, We know that, [tex]\bf{\underline {\star \: Product \:of\:zeroes \::}}\\[/tex] ⠀⠀⠀⠀[tex]\bf{ \alpha \times \beta = \bigg( \dfrac{Constant\:Term}{Cofficient \:of\:x^2}\bigg) }\\\\[/tex] ⠀⠀⠀⠀⠀⠀[tex]\underline {\frak{\star\:Now \: By \: Substituting \: the \: known \: Cofficients\::}}\\[/tex] [tex]:\implies\bf { \alpha \times \beta = \bigg( \dfrac{1}{5}\bigg) }\\\\[/tex] ⠀⠀⠀⠀⠀━━━━━━━━━━━━━━━━━━━⠀ ⠀⠀⠀⠀⠀⠀⠀⠀Finding ⠀[tex] \alpha ^{2} + \beta ^{2} [/tex] . [tex]:\implies\sf { \alpha^2 + \beta^2 }\\\\[/tex] As, We know that , [tex]Algebraic\:Indentity\::\:(a+b)^2 = a^2 + b^2 + 2ab [/tex] Or , [tex] a^2 + b^2 = (a+b)^2 – 2ab [/tex] Then , ⠀⠀⠀⠀[tex]:\implies\sf { \alpha^2 + \beta^2 = \bigg( \alpha + \beta\bigg)^2 – 2\alpha\beta }\\\\[/tex] ⠀⠀⠀⠀⠀⠀[tex]\underline {\frak{\star\:Now \: By \: Substituting \: the \: Found \: Values \::}}\\[/tex] ⠀⠀⠀⠀[tex]:\implies\sf { \alpha^2 + \beta^2 = \bigg( \alpha + \beta\bigg)^2 – 2\alpha\beta }\\\\[/tex] ⠀⠀⠀⠀[tex]:\implies\sf { \alpha^2 + \beta^2 = \bigg( -1\bigg)^2 – 2\times \dfrac{1}{5} }\\\\[/tex] ⠀⠀⠀⠀[tex]:\implies\sf { \alpha^2 + \beta^2 = 1 – \dfrac{2}{5} }\\\\[/tex] ⠀⠀⠀⠀[tex]:\implies\sf { \alpha^2 + \beta^2 = \dfrac{5 – 2}{5} }\\\\[/tex] ⠀⠀⠀⠀[tex]:\implies\bf { \alpha^2 + \beta^2 = \dfrac{3}{5} }\qquad \longrightarrow\bf{AnswEr}\\\\\\[/tex] ⠀⠀⠀⠀⠀━━━━━━━━━━━━━━━━━━━⠀ Reply
Given Equation : p(x) = 5x² + 5x + 1 Have to find the value of the [tex] {\sf{ \alpha ^{2} + \beta ^{2} }} [/tex] Here, Coefficient of x² → 5 Coefficient of x = 5 Constant term = 1 Relation between zeroes and coefficients [tex] \textsf{Sum of the Zeroes } [/tex] [tex]\longrightarrow\sf – {Coefficient \: of \: x/Coefficient \: of \: x^{2}}[/tex] [tex]:\implies \sf{ \alpha + \beta = \dfrac{- 5}{5}}\\ \\ [/tex] [tex]:\implies \sf{ \alpha + \beta = – 1 }\\ \\ [/tex] _________________________ [tex]\textsf{Product of the Zeroes } [/tex] [tex]\longrightarrow\sf{Constant \: Term/Coefficient \: of \: x^{2}}[/tex] [tex]:\implies \sf{ \alpha \times \beta = \dfrac{1}{5} } \\ \\ [/tex] Now, First we going to use the algebraic identity : [tex]\bullet\sf {a^{2} + b^{2} = ( a + b )^{2} – 2ab} \\ [/tex] (Putting values in the given Equation : [tex]\rightarrow \sf \alpha ^{2} + \beta ^{2} \\ \\ [/tex] (-1)² – (2 × (-1) × 1/5) [tex]\rightarrow \sf 1 – \dfrac{2}{5} \\ \\ [/tex] [tex]\rightarrow \sf \dfrac{5 -2}{5} \\ \\ [/tex] [tex]\rightarrow \sf \dfrac{3}{5} \\ \\ [/tex] Hence, The value of α² + β² is : [tex]{\boxed{\therefore{\sf{ \dfrac{3}{5}}}}} \\ \\ [/tex] _________________________ ⠀⠀⠀⠀⠀⠀⠀⠀⠀ Reply
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀☆ GIVEN⠀ POLYNOMIAL – p(x) = 5x² + 5x + 1 :
⠀⠀⠀⠀⠀━━━━━━━━━━━━━━━━━━━⠀
⠀⠀⠀⠀⠀The Cofficients of Polynomial p(x) = 5x² + 5x + 1 :
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Given that,
As, We know that ,
[tex]\bf{\underline {\star \: Sum \:of\:zeroes \::}}\\[/tex]
⠀⠀⠀⠀⠀⠀[tex]\underline {\frak{\star\:Now \: By \: Substituting \: the \: known \: Cofficients\::}}\\[/tex]
⠀⠀⠀⠀[tex]:\implies\sf { \alpha + \beta = \bigg( \dfrac{-5}{5}\bigg) }\\\\[/tex]
⠀⠀⠀⠀[tex]:\implies\sf { \alpha + \beta = \bigg( \cancel {\dfrac{-5}{5}}\bigg) }\\\\[/tex]
⠀⠀⠀⠀[tex]:\implies\bf { \alpha + \beta = -1 }\\\\[/tex]
And,
As, We know that,
[tex]\bf{\underline {\star \: Product \:of\:zeroes \::}}\\[/tex]
⠀⠀⠀⠀[tex]\bf{ \alpha \times \beta = \bigg( \dfrac{Constant\:Term}{Cofficient \:of\:x^2}\bigg) }\\\\[/tex]
⠀⠀⠀⠀⠀⠀[tex]\underline {\frak{\star\:Now \: By \: Substituting \: the \: known \: Cofficients\::}}\\[/tex]
[tex]:\implies\bf { \alpha \times \beta = \bigg( \dfrac{1}{5}\bigg) }\\\\[/tex]
⠀⠀⠀⠀⠀━━━━━━━━━━━━━━━━━━━⠀
⠀⠀⠀⠀⠀⠀⠀⠀Finding ⠀[tex] \alpha ^{2} + \beta ^{2} [/tex] .
[tex]:\implies\sf { \alpha^2 + \beta^2 }\\\\[/tex]
As, We know that ,
Or ,
Then ,
⠀⠀⠀⠀[tex]:\implies\sf { \alpha^2 + \beta^2 = \bigg( \alpha + \beta\bigg)^2 – 2\alpha\beta }\\\\[/tex]
⠀⠀⠀⠀⠀⠀[tex]\underline {\frak{\star\:Now \: By \: Substituting \: the \: Found \: Values \::}}\\[/tex]
⠀⠀⠀⠀[tex]:\implies\sf { \alpha^2 + \beta^2 = \bigg( \alpha + \beta\bigg)^2 – 2\alpha\beta }\\\\[/tex]
⠀⠀⠀⠀[tex]:\implies\sf { \alpha^2 + \beta^2 = \bigg( -1\bigg)^2 – 2\times \dfrac{1}{5} }\\\\[/tex]
⠀⠀⠀⠀[tex]:\implies\sf { \alpha^2 + \beta^2 = 1 – \dfrac{2}{5} }\\\\[/tex]
⠀⠀⠀⠀[tex]:\implies\sf { \alpha^2 + \beta^2 = \dfrac{5 – 2}{5} }\\\\[/tex]
⠀⠀⠀⠀[tex]:\implies\bf { \alpha^2 + \beta^2 = \dfrac{3}{5} }\qquad \longrightarrow\bf{AnswEr}\\\\\\[/tex]
⠀⠀⠀⠀⠀━━━━━━━━━━━━━━━━━━━⠀
Given Equation :
Have to find the value of the [tex] {\sf{ \alpha ^{2} + \beta ^{2} }} [/tex]
Here,
Relation between zeroes and coefficients
[tex] \textsf{Sum of the Zeroes } [/tex]
[tex]\longrightarrow\sf – {Coefficient \: of \: x/Coefficient \: of \: x^{2}}[/tex]
[tex]:\implies \sf{ \alpha + \beta = \dfrac{- 5}{5}}\\ \\ [/tex]
[tex]:\implies \sf{ \alpha + \beta = – 1 }\\ \\ [/tex]
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[tex]\textsf{Product of the Zeroes } [/tex]
[tex]\longrightarrow\sf{Constant \: Term/Coefficient \: of \: x^{2}}[/tex]
[tex]:\implies \sf{ \alpha \times \beta = \dfrac{1}{5} } \\ \\ [/tex]
Now,
First we going to use the algebraic identity :
[tex]\bullet\sf {a^{2} + b^{2} = ( a + b )^{2} – 2ab} \\ [/tex]
(Putting values in the given Equation :
[tex]\rightarrow \sf \alpha ^{2} + \beta ^{2} \\ \\ [/tex]
(-1)² – (2 × (-1) × 1/5)
[tex]\rightarrow \sf 1 – \dfrac{2}{5} \\ \\ [/tex]
[tex]\rightarrow \sf \dfrac{5 -2}{5} \\ \\ [/tex]
[tex]\rightarrow \sf \dfrac{3}{5} \\ \\ [/tex]
Hence,
The value of α² + β² is :
[tex]{\boxed{\therefore{\sf{ \dfrac{3}{5}}}}} \\ \\ [/tex]
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