Algebra
Calculus
Trigonometry
Matrix
Question
Simplify the expression
−2k−56k4
Evaluate
−2k−7×8k4
Solution
−2k−56k4
Show Solution
Factor the expression
−2k(1+28k3)
Evaluate
−2k−7×8k4
Multiply the numbers
More Steps
Evaluate
7×8
Multiply the numbers
56
Evaluate
56k4
−2k−56k4
Rewrite the expression
−2k−2k×28k3
Solution
−2k(1+28k3)
Show Solution
Find the roots
k1=−14398,k2=0
Alternative Form
k1≈−0.329317,k2=0
Evaluate
−2k−7(8k4)
To find the roots of the expression,set the expression equal to 0
−2k−7(8k4)=0
Multiply the terms
−2k−7×8k4=0
Multiply the numbers
−2k−56k4=0
Factor the expression
−2k(1+28k3)=0
Divide both sides
k(1+28k3)=0
Separate the equation into 2 possible cases
k=01+28k3=0
Solve the equation
More Steps
Evaluate
1+28k3=0
Move the constant to the right-hand side and change its sign
28k3=0−1
Removing 0 doesn't change the value,so remove it from the expression
28k3=−1
Divide both sides
2828k3=28−1
Divide the numbers
k3=28−1
Use b−a=−ba=−ba to rewrite the fraction
k3=−281
Take the 3-th root on both sides of the equation
3k3=3−281
Calculate
k=3−281
Simplify the root
More Steps
Evaluate
3−281
An odd root of a negative radicand is always a negative
−3281
To take a root of a fraction,take the root of the numerator and denominator separately
−32831
Simplify the radical expression
−3281
Multiply by the Conjugate
328×3282−3282
Simplify
328×3282−2398
Multiply the numbers
28−2398
Cancel out the common factor 2
14−398
Calculate
−14398
k=−14398
k=0k=−14398
Solution
k1=−14398,k2=0
Alternative Form
k1≈−0.329317,k2=0
Show Solution