Question
Simplify the expression
t4−20t2
Evaluate
t4−5t2×4
Solution
t4−20t2
Show Solution

Factor the expression
t2(t2−20)
Evaluate
t4−5t2×4
Multiply the terms
t4−20t2
Rewrite the expression
t2×t2−t2×20
Solution
t2(t2−20)
Show Solution

Find the roots
t1=−25,t2=0,t3=25
Alternative Form
t1≈−4.472136,t2=0,t3≈4.472136
Evaluate
t4−5t2×4
To find the roots of the expression,set the expression equal to 0
t4−5t2×4=0
Multiply the terms
t4−20t2=0
Factor the expression
t2(t2−20)=0
Separate the equation into 2 possible cases
t2=0t2−20=0
The only way a power can be 0 is when the base equals 0
t=0t2−20=0
Solve the equation
More Steps

Evaluate
t2−20=0
Move the constant to the right-hand side and change its sign
t2=0+20
Removing 0 doesn't change the value,so remove it from the expression
t2=20
Take the root of both sides of the equation and remember to use both positive and negative roots
t=±20
Simplify the expression
More Steps

Evaluate
20
Write the expression as a product where the root of one of the factors can be evaluated
4×5
Write the number in exponential form with the base of 2
22×5
The root of a product is equal to the product of the roots of each factor
22×5
Reduce the index of the radical and exponent with 2
25
t=±25
Separate the equation into 2 possible cases
t=25t=−25
t=0t=25t=−25
Solution
t1=−25,t2=0,t3=25
Alternative Form
t1≈−4.472136,t2=0,t3≈4.472136
Show Solution
