Mathematics · Quantitative Aptitude
Equations and Roots
69 Questions
Equations and roots questions cover finding real solutions to algebraic, trigonometric, and polynomial equations. They are fundamental for advanced mathematics sections. Practicing these problems ensures quick recognition of underlying patterns and calculation shortcuts.
polynomial equationssystem of equationstrigonometric equationsabsolute value equations
Equations and Roots Questions
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there are no answers
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one
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two
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more than two
C
Correct answer
Explanation
The equation x^2 = 196 has two solutions: x = 14 and x = -14.
The number of solutions of equation $z^{10}-z^{5}+1=0$ are
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only two solution
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No solution
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only five solution
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exactly 10
D
Correct answer
Explanation
${ z }^{ 10 }-{ z }^{ 5 }+1=0$
Let ${ z }^{ 5 }=w$
$\Rightarrow { w }^{ 2 }-w+1=0$
$\Rightarrow w=\frac { 1\pm \sqrt { 3 } }{ 2 } =\cos { \frac { \Pi }{ 3 } } \pm \sin { \frac { \Pi }{ 3 } } =cis\left( \pm \frac { \Pi }{ 3 } \right) $
$\Rightarrow { z }^{ 5 }=cis\left( \pm \frac { \Pi }{ 3 } \right) $
Case 1:
${ z }^{ 5 }=cis\left( \frac { \Pi }{ 3 } \right) $
$\Rightarrow z={ \left( cis\left( \frac { \Pi }{ 3 } \right) \right) }^{ \frac { 1 }{ 5 } }=cis\left( \frac { 2k\Pi +\Pi }{ 15 } \right) \ $ ...{De Moivre's Theorem}
Where k=0,1,2,3,4.
Therefore number of solutions are 5.
Case 2:
${ z }^{ 5 }=cis\left( -\frac { \Pi }{ 3 } \right) $
$\Rightarrow z={ \left( cis\left( -\frac { \Pi }{ 3 } \right) \right) }^{ \frac { 1 }{ 5 } }=cis\left( \frac { 2k\Pi -\Pi }{ 15 } \right) $ ...{De Moivre's Theorem}
Where k=0,1,2,3,4.
Therefore number of solutions are 5.
From case 1 & case 2 total number of solutions of equation ${ z }^{ 10 }-{ z }^{ 5 }+1=0$ are 10.
Ans: D
What is the name of the theorem that Shorey proved in 1973, which provides a lower bound for the number of solutions to the Thue equation $x^m - y^n = c$?
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Shorey's Theorem
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Baker's Theorem
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Siegel's Theorem
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Fermat's Last Theorem
A
Correct answer
Explanation
Shorey's Theorem states that the number of solutions to the Thue equation $x^m - y^n = c$ is at least $c^{1/m} + c^{1/n} - 1$.
In 1982, Shorey and what other mathematician proved that the Diophantine equation $x^2 - Dy^2 = 4$ has infinitely many solutions for any square-free integer $D > 0$?
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S. S. Pillai
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K. S. Nagaraja
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R. Balasubramanian
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M. N. Gopalan
C
Correct answer
Explanation
Shorey and Balasubramanian proved this result by using a method based on modular forms and the theory of quadratic forms.
What is the name of the theorem that Shorey and R. Tijdeman proved in 1986, which provides a lower bound for the number of solutions to the equation $x^m + y^n = z^k$?
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The Shorey-Tijdeman Theorem
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The Baker-Tijdeman Theorem
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The Siegel-Tijdeman Theorem
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The Fermat-Tijdeman Theorem
A
Correct answer
Explanation
The Shorey-Tijdeman Theorem states that the number of solutions to the equation $x^m + y^n = z^k$ is at least $c^{1/m} + c^{1/n} + c^{1/k} - 3$.
In 2000, Shorey and what other mathematician proved that the Diophantine equation $x^2 - Dy^2 = 5$ has infinitely many solutions for any square-free integer $D > 0$?
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S. S. Pillai
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K. S. Nagaraja
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R. Balasubramanian
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M. N. Gopalan
D
Correct answer
Explanation
Shorey and Gopalan proved this result by using a method based on modular forms and the theory of quadratic forms.
What is the name of the theorem that Shorey and T. N. Venkataramana proved in 2005, which provides a lower bound for the number of solutions to the equation $x^m + y^n = z^k$ in positive integers?
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The Shorey-Venkataramana Theorem
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The Baker-Venkataramana Theorem
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The Siegel-Venkataramana Theorem
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The Fermat-Venkataramana Theorem
A
Correct answer
Explanation
The Shorey-Venkataramana Theorem states that the number of solutions to the equation $x^m + y^n = z^k$ in positive integers is at least $c^{1/m} + c^{1/n} + c^{1/k} - 4$.
In 2020, Shorey and what other mathematician proved that the Diophantine equation $x^2 - Dy^2 = 6$ has infinitely many solutions for any square-free integer $D > 0$?
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S. S. Pillai
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K. S. Nagaraja
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R. Balasubramanian
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M. N. Gopalan
C
Correct answer
Explanation
Shorey and Balasubramanian proved this result by using a method based on modular forms and the theory of quadratic forms.
What is the genus of the Riemann surface defined by the equation $y^2 = x^3 + x + 1$?
B
Correct answer
Explanation
The genus of a Riemann surface is a topological invariant that is related to the number of holes in the surface. In this case, the Riemann surface defined by the equation $y^2 = x^3 + x + 1$ has one hole, so its genus is 1.
What is the dimension of the variety defined by the equation $x^2 + y^2 + z^2 = 1$?
C
Correct answer
Explanation
The dimension of a variety is the number of independent variables that are needed to parameterize it. In this case, the variety defined by the equation $x^2 + y^2 + z^2 = 1$ is a sphere, which is a two-dimensional surface. So its dimension is 2.
Let $f(x) = x^3 - 3x^2 + 2x + 1$. Find the number of real solutions of the equation $f(x) = f(f(x))$.
B
Correct answer
Explanation
Let $y = f(x)$. Then the equation $f(x) = f(f(x))$ becomes $y = f(y)$. This is a quadratic equation in $y$. Solving for $y$, we get $y = 1$ or $y = 2$. Therefore, there are two real solutions of the equation $f(x) = f(f(x))$.
Let $f(x) = x^3 - 3x^2 + 2x + 1$. Find the number of real solutions of the equation $f(x) = f(f(x))$.
B
Correct answer
Explanation
Let $y = f(x)$. Then the equation $f(x) = f(f(x))$ becomes $y = f(y)$. This is a quadratic equation in $y$. Solving for $y$, we get $y = 1$ or $y = 2$. Therefore, there are two real solutions of the equation $f(x) = f(f(x))$.
Let $f(x) = x^3 - 3x^2 + 2x + 1$. Find the number of real solutions of the equation $f(x) = f(f(x))$.
B
Correct answer
Explanation
Let $y = f(x)$. Then the equation $f(x) = f(f(x))$ becomes $y = f(y)$. This is a quadratic equation in $y$. Solving for $y$, we get $y = 1$ or $y = 2$. Therefore, there are two real solutions of the equation $f(x) = f(f(x))$.
What is the Birch and Swinnerton-Dyer Conjecture?
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The number of rational points on an elliptic curve is finite.
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The number of rational points on an elliptic curve is infinite.
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The number of rational points on an elliptic curve is equal to the number of integer solutions to a certain Diophantine equation.
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The number of rational points on an elliptic curve is equal to the number of complex solutions to a certain Diophantine equation.
C
Correct answer
Explanation
The Birch and Swinnerton-Dyer Conjecture states that the number of rational points on an elliptic curve is equal to the number of integer solutions to a certain Diophantine equation.
Which of the following is not a method for solving quintic equations?
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Abel's method
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Galois' method
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Lagrange's method
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Newton's method
D
Correct answer
Explanation
Newton's method is a numerical method for solving equations, including quintic equations. It is not a specific method for solving quintic equations like Abel's method, Galois' method, or Lagrange's method.