answersLogoWhite

0


Best Answer

Extraneous solutions turn up in a few different p;aces in algebra. One reason they turn up in logarithmic equations is that you can only have a log of a positive number, but when you solve the equation, one of the answers is negative.

Did you ever do a word problem about a rectangle and have to solve a quadratic equation? You probably got 2 answers, and had to reject one of them because the length of a rectangle can't be negative. Same idea: the algebra doesn't understand what the problem is about, it just churns out answers!

User Avatar

Wiki User

11y ago
This answer is:
User Avatar

Add your answer:

Earn +20 pts
Q: Why can there be extraneous solutions in a logartithmic equation?
Write your answer...
Submit
Still have questions?
magnify glass
imp
Continue Learning about Math & Arithmetic

What does extraneous mean What must you do to determine whether a solution is an extraneous solution?

Extraneous means extra and unnecessary. Extraneous solutions are values that can arise from the process of solving the equation but do not in fact satisfy the initial equation. These solutions occur most often when not all parts of the process of solving are not completely reversible - for example, if both sides of the equation are squared at some point.


What is a solution of an eqaution derived from an original equation that is not a solution of the original equation?

Extraneous solution


What must you do to determine weather a soluion is an exraneous solution?

If the solution, makes the denominator equal to zero, makes the expression of a logarithm or under a square root, a negative one. If there are more than one denominator, check all the solutions. Usually, we determine the extraneous solutions before we solve the equation.


Which pairs are solutions to the equation?

That depends on the equation.


How can you determine whether a polynomial equation has imaginary solutions?

To determine whether a polynomial equation has imaginary solutions, you must first identify what type of equation it is. If it is a quadratic equation, you can use the quadratic formula to solve for the solutions. If the equation is a cubic or higher order polynomial, you can use the Rational Root Theorem to determine if there are any imaginary solutions. The Rational Root Theorem states that if a polynomial equation has rational solutions, they must be a factor of the constant term divided by a factor of the leading coefficient. If there are no rational solutions, then the equation has imaginary solutions. To use the Rational Root Theorem, first list out all the possible rational solutions. Then, plug each possible rational solution into the equation and see if it is a solution. If there are any solutions, then the equation has imaginary solutions. If not, then there are no imaginary solutions.

Related questions

What is the extraneous solution to w equals sqrt 7w?

An "extraneous solution" is not a characteristic of an equation, but has to do with the methods used to solve it. Typically, if you square both sides of the equation, and solve the resulting equation, you might get additional solutions that are not part of the original equation. Just do this, and check each of the solutions, whether it satisfies the original equation. If one of them doesn't, it is an "extraneous" solution introduced by the squaring.


What does extraneous mean What must you do to determine whether a solution is an extraneous solution?

Extraneous means extra and unnecessary. Extraneous solutions are values that can arise from the process of solving the equation but do not in fact satisfy the initial equation. These solutions occur most often when not all parts of the process of solving are not completely reversible - for example, if both sides of the equation are squared at some point.


Why is it necessary to check for extraneous solutions in radical equations?

1) When solving radical equations, it is often convenient to square both sides of the equation. 2) When doing this, extraneous solutions may be introduced - the new equation may have solutions that are not solutions of the original equation. Here is a simple example (without radicals): The equation x = 5 has exactly one solution (if you replace x with 5, the equation is true, for other values, it isn't). If you square both sides, you get: x2 = 25 which also has the solution x = 5. However, it also has the extraneous solution x = -5, which is not a solution to the original equation.


In general when solving a radical equation should you first isolate the radical and then both sides?

It often helps to isolate the radical, and then square both sides. Beware of extraneous solutions - the new equation may have solutions that are not part of the solutions of the original equation, so you definitely need to check any purported solutions with the original equation.


A solution that does not satisfy the original equation?

an extraneous solution.


Is one solution to a real-world problem involving a quadratic equation always extraneous?

No. Sometimes they are both extraneous.


What are the steps to solving a radical equation?

Details may vary depending on the equation. Quite often, you have to square both sides of the equation, to get rid of the radical sign. It may be necessary to rearrange the equation before doing this, after doing this, or both. Squaring both sides of the equation may introduce "extraneous" roots (solutions), that is, solutions that are not part of the original equation, so you have to check each solution of the second equation, to see whether it is also a solution of the first equation.


What is a solution of an eqaution derived from an original equation that is not a solution of the original equation?

Extraneous solution


What happens if you are checking a solution for the radical expression and find that it makes one of the denominators in the expression equal to zero?

Then it is not a solution of the original equation. It is quite common, when solving equations involving radicals, or even when solving equations with fractions, that "extraneous" solutions are added in the converted equation - additional solutions that are not solutions of the original equation. For example, when you multiply both sides of an equation by a factor (x-1), this is valid EXCEPT for the case that x = 1. Therefore, in this example, if x = 1 is a solution of the transformed equation, it may not be a solution to the original equation.


What is a extraneous solution?

A solution to an equation that you get at the end of whatever method you use that does not actually solve the original equation. One well-known example:1=2 ====>0=0 Therefore, one equals two.x0 x0The laws of algebra says that we can do this because we multiplied both sides by zero. Logically, we all know this isn't actually true. This is what extraneous solutions look like when solving linear equations:2x+3=9 If you assume x=1... 2(1)+3=9 ...and multiply everything by 0...0=0. Therefore, my guess is correct and x=1.


What is an extraneous solution of an equation?

when you solve a questiom, you get an answer. If you chect your answer by substituting the value of the variable in the question and you don't get L.H.S and R.H.S equal then your answer is called extraneous solution.


If an equation is an identity how many solutions does it have?

An identity equation has infinite solutions.