Find the equation whose one root is square of the sum and the other root is square of the difference of the roots of the equation 2x² + 2 (m + n) x + m² + n² = 0.
Answers
Answer:
Question :-
Form the quadratic equation whose roots are the squares of the sum of roots and square
of the difference of roots of the equation
2x² + 2(m+n)x + m² + n² = 0
Answer :-
→ x² - (4mn)x + (m² - n²)² = 0
To Find :-
→ A quadratic equation whose roots are square of the sum of roots and square of the difference of roots of given quadratic.
Solution :-
Let a and b are the roots of required quadratic equation,
→ a = square of the sum of roots of the given polynomial
→ b = square of the difference of roots of the given polynomial.
We have ,
→ 2x² + 2(m+n)x + m² + n² = 0
Hence ,
\begin{gathered} \sf let \: \alpha \: and \: \beta \: are \: the \: roots \: of \: given \: \\ \sf polynomial \\ \to \sf sum \: of \: roots \: = - \frac{coefficient \: of \: x}{ coefficient \: of \: {x}^{2} } \\ \\ \to \sf \alpha + \beta = - \frac{2(m + n)}{2} \\ \\ \to \boxed{ \sf \alpha + \beta \: = - (m + n)} \\ \\ \sf \: product \: of \: roots \: = \frac{constant \: }{ coefficient \: of \: {x}^{2} } \\ \\ \to \boxed{\sf\alpha \beta \: = \frac{ {m}^{2} + {n}^{2} }{2} }\end{gathered}
letαandβaretherootsofgiven
polynomial
→sumofroots=−
coefficientofx
2
coefficientofx
→α+β=−
2
2(m+n)
→
α+β=−(m+n)
productofroots=
coefficientofx
2
constant
→
αβ=
2
m
2
+n
2
Hence ,
\begin{gathered} \to \sf \: a = { (\alpha + \beta)}^{2} \\ \\ \to \sf \: a = { \{ - (m + n) \}}^{2} \\ \\ \to \boxed{ \sf \: a = {(m + n)}^{2} } \\ \\ \bf and \: \\ \to \sf \: b = {( \alpha - \beta)}^{2} \\ \\ \to \sf b = {( \alpha + \beta)}^{2} - 4 \alpha \beta \\ \\ \to \sf \: b = {(m + n)}^{2} - 2( {m}^{2} + {n}^{2} ) \\ \\ \to \sf \: b = {m}^{2} + {n}^{2} + 2mn \: - 2 {m}^{2} - 2 {n}^{2} \\ \\ \to \sf \: \boxed{ \sf \: b = - {(m - n)}^{2} }\end{gathered}
→a=(α+β)
2
→a={−(m+n)}
2
→
a=(m+n)
2
and
→b=(α−β)
2
→b=(α+β)
2
−4αβ
→b=(m+n)
2
−2(m
2
+n
2
)
→b=m
2
+n
2
+2mn−2m
2
−2n
2
→
b=−(m−n)
2
hence , required equation is
→ x² - (a + b)x + ab = 0
\begin{gathered} \sf \: hence \: a + b = {(m + n)}^{2} - {(m - n)}^{2} \\ \\ \to \sf \: a + b = {m}^{2} + {n}^{2} + 2mn - {m}^{2} - {n}^{2} + 2mn \\ \\ \to \boxed{ \sf a + b = 4mn} \\ \\ \sf \: and \: \\ \to \sf ab = - {(m + n)}^{2} {(m - n)}^{2} \\ \\ \to \boxed{\sf \: ab = {( {m}^{2} - {n}^{2} )}^{2} }\end{gathered}
hencea+b=(m+n)
2
−(m−n)
2
→a+b=m
2
+n
2
+2mn−m
2
−n
2
+2mn
→
a+b=4mn
and
→ab=−(m+n)
2
(m−n)
2
→
ab=(m
2
−n
2
)
2
→ x² - (4mn)x + (m² - n²)² = 0
Question :-
Form the quadratic equation whose roots are the squares of the sum of roots and square
of the difference of roots of the equation
2x² + 2(m+n)x + m² + n² = 0
Answer :-
→ x² - (4mn)x + (m² - n²)² = 0
To Find :-
→ A quadratic equation whose roots are square of the sum of roots and square of the difference of roots of given quadratic.
Solution :-
Let a and b are the roots of required quadratic equation,
→ a = square of the sum of roots of the given polynomial
→ b = square of the difference of roots of the given polynomial.
We have ,
→ 2x² + 2(m+n)x + m² + n² = 0
Hence ,
Hence ,
hence , required equation is
→ x² - (a + b)x + ab = 0
→ x² - (4mn)x + (m² - n²)² = 0
Hope it helps