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(k^4_3_3k^3)+(-5k^3+6k^3_8k^5)

User Aleks
by
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1 Answer

4 votes

Answer:

(k4+3+3k3)+(-5k3+6k3+8k5)

Final result :

8k5 + k4 + 4k3 + 3

Step by step solution :

Step 1 :

Equation at the end of step 1 :

(((k4)+3)+(3•(k3)))+(((0-(5•(k3)))+(6•(k3)))+23k5)

Step 2 :

Equation at the end of step 2 :

(((k4)+3)+(3•(k3)))+(((0-(5•(k3)))+(2•3k3))+23k5)

Step 3 :

Equation at the end of step 3 :

(((k4)+3)+(3•(k3)))+(((0-5k3)+(2•3k3))+23k5)

Step 4 :

Equation at the end of step 4 :

(((k4) + 3) + 3k3) + (8k5 + k3)

Step 5 :

Checking for a perfect cube :

5.1 8k5+k4+4k3+3 is not a perfect cube


Trying to factor by pulling out :

5.2 Factoring: 8k5+k4+4k3+3


Thoughtfully split the expression at hand into groups, each group having two terms :


Group 1: k4+3

Group 2: 8k5+4k3


Pull out from each group separately :


Group 1: (k4+3) • (1)

Group 2: (2k2+1) • (4k3)


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 :

5.3 Find roots (zeroes) of : F(k) = 8k5+k4+4k3+3

Polynomial Roots Calculator is a set of methods aimed at finding values of k for which F(k)=0


Rational Roots Test is one of the above mentioned tools. It would only find Rational Roots that is numbers k 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 8 and the Trailing Constant is 3.


The factor(s) are:


of the Leading Coefficient : 1,2 ,4 ,8

of the Trailing Constant : 1 ,3


Let us test ....


P Q P/Q F(P/Q) Divisor

-1 1 -1.00 -8.00

-1 2 -0.50 2.31

-1 4 -0.25 2.93

-1 8 -0.13 2.99

-3 1 -3.00 -1968.00

-3 2 -1.50 -66.19

-3 4 -0.75 -0.27

-3 8 -0.38 2.75

1 1 1.00 16.00

1 2 0.50 3.81

1 4 0.25 3.07

1 8 0.13 3.01

3 1 3.00 2136.00

3 2 1.50 82.31

3 4 0.75 6.90

3 8 0.38 3.29


Polynomial Roots Calculator found no rational roots


Final result :

8k5 + k4 + 4k3 + 3

Explanation:


User Reddy
by
7.6k points