Can the polynomial equation $x^8-x^7+x^2-x+15=0$ have real roots?

In summary, the "Nature of roots challenge" is a mathematical problem that involves finding the roots of a quadratic equation. It can be solved using the quadratic formula, factoring, or completing the square method. The challenge can have three types of roots: two distinct real roots, one repeated real root, or two complex roots. Solving this challenge can help in understanding the behavior and applications of quadratic equations in fields such as physics, finance, and engineering. Some shortcuts and tricks, such as using the discriminant or patterns and properties of quadratic equations, can also be used to solve this challenge.
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Prove that the polynomial equation $x^8-x^7+x^2-x+15=0$ has no real solution.
 
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We have $x^8-x^7 + x^2 -x + 15 = x^7(x-1) + x(x-1) + 15$

each term is positive for $x > 1$ so LHS is greater than 0 so no solution for $ x > 1$

for x = 1 LHS = 15 so x = 1 is not a solution

Further $x^8-x^7 + x^2 -x + 15 = (15- x) + x^2(1-x^5) + x^8 $

Each term is positive for $x < 1$ so LHS is greater than 0 so no solution for $ x < 1$

Hence no real solution
 

What is the "Nature of roots challenge"?

The "Nature of roots challenge" is a mathematical problem that involves finding the roots of a given polynomial equation. It is a common problem in algebra and is used to test students' understanding of the properties of roots and their relationship to the coefficients of the equation.

What are roots?

Roots, also known as solutions or zeros, are the values of the variable that make the polynomial equation equal to zero. In other words, they are the values that satisfy the equation and can be found by substituting the variable with the given values.

How can I solve the "Nature of roots challenge"?

To solve the "Nature of roots challenge", you can use various methods such as factoring, the quadratic formula, or completing the square. These methods involve manipulating the coefficients of the equation to find the values of the roots.

What are the different types of roots?

There are three types of roots: real, imaginary, and complex. Real roots are the values of the variable that are real numbers, while imaginary roots are the values that involve the imaginary unit, i. Complex roots are a combination of real and imaginary roots.

Why is the "Nature of roots challenge" important?

The "Nature of roots challenge" is important because it helps in understanding the fundamental concepts of algebra, such as factoring and solving equations. It also has real-world applications, such as in engineering and physics, where polynomial equations are used to model various phenomena.

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