Solution - Adding, subtracting and finding the least common multiple
Other Ways to Solve
Adding, subtracting and finding the least common multipleStep by Step Solution
Step 1 :
5
Simplify —————————————
x2 - 10x - 25
Trying to factor by splitting the middle term
1.1 Factoring x2 - 10x - 25
The first term is, x2 its coefficient is 1 .
The middle term is, -10x its coefficient is -10 .
The last term, "the constant", is -25
Step-1 : Multiply the coefficient of the first term by the constant 1 • -25 = -25
Step-2 : Find two factors of -25 whose sum equals the coefficient of the middle term, which is -10 .
| -25 | + | 1 | = | -24 | ||
| -5 | + | 5 | = | 0 | ||
| -1 | + | 25 | = | 24 |
Observation : No two such factors can be found !!
Conclusion : Trinomial can not be factored
Equation at the end of step 1 :
5
x - —————————————
x2 - 10x - 25
Step 2 :
Rewriting the whole as an Equivalent Fraction :
2.1 Subtracting a fraction from a whole
Rewrite the whole as a fraction using (x2-10x-25) as the denominator :
x x • (x2 - 10x - 25)
x = — = ———————————————————
1 (x2 - 10x - 25)
Equivalent fraction : The fraction thus generated looks different but has the same value as the whole
Common denominator : The equivalent fraction and the other fraction involved in the calculation share the same denominator
Adding fractions that have a common denominator :
2.2 Adding up the two equivalent fractions
Add the two equivalent fractions which now have a common denominator
Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:
x • (x2-10x-25) - (5) x3 - 10x2 - 25x - 5
————————————————————— = ———————————————————
1 • (x2-10x-25) 1 • (x2 - 10x - 25)
Checking for a perfect cube :
2.3 x3 - 10x2 - 25x - 5 is not a perfect cube
Trying to factor by pulling out :
2.4 Factoring: x3 - 10x2 - 25x - 5
Thoughtfully split the expression at hand into groups, each group having two terms :
Group 1: -25x - 5
Group 2: -10x2 + x3
Pull out from each group separately :
Group 1: (5x + 1) • (-5)
Group 2: (x - 10) • (x2)
Bad news !! Factoring by pulling out fails :
The groups have no common factor and can not be added up to form a multiplication.
Polynomial Roots Calculator :
2.5 Find roots (zeroes) of : F(x) = x3 - 10x2 - 25x - 5
Polynomial Roots Calculator is a set of methods aimed at finding values of x for which F(x)=0
Rational Roots Test is one of the above mentioned tools. It would only find Rational Roots that is numbers x which can be expressed as the quotient of two integers
The Rational Root Theorem states that if a polynomial zeroes for a rational number P/Q then P is a factor of the Trailing Constant and Q is a factor of the Leading Coefficient
In this case, the Leading Coefficient is 1 and the Trailing Constant is -5.
The factor(s) are:
of the Leading Coefficient : 1
of the Trailing Constant : 1 ,5
Let us test ....
| P | Q | P/Q | F(P/Q) | Divisor | |||||
|---|---|---|---|---|---|---|---|---|---|
| -1 | 1 | -1.00 | 9.00 | ||||||
| -5 | 1 | -5.00 | -255.00 | ||||||
| 1 | 1 | 1.00 | -39.00 | ||||||
| 5 | 1 | 5.00 | -255.00 |
Polynomial Roots Calculator found no rational roots
Final result :
x3 + 10x2 + 25x + 5
———————————————————
x2 + 10x + 25
How did we do?
Please leave us feedback.