Question
Simplify the expression
x4−3x2−3
Evaluate
x3×x−3x2−3
Solution
More Steps

Evaluate
x3×x
Use the product rule an×am=an+m to simplify the expression
x3+1
Add the numbers
x4
x4−3x2−3
Show Solution

Find the roots
x1=−26+221,x2=26+221
Alternative Form
x1≈−1.947123,x2≈1.947123
Evaluate
x3×x−3x2−3
To find the roots of the expression,set the expression equal to 0
x3×x−3x2−3=0
Multiply the terms
More Steps

Evaluate
x3×x
Use the product rule an×am=an+m to simplify the expression
x3+1
Add the numbers
x4
x4−3x2−3=0
Solve the equation using substitution t=x2
t2−3t−3=0
Substitute a=1,b=−3 and c=−3 into the quadratic formula t=2a−b±b2−4ac
t=23±(−3)2−4(−3)
Simplify the expression
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Evaluate
(−3)2−4(−3)
Multiply the numbers
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Evaluate
4(−3)
Multiplying or dividing an odd number of negative terms equals a negative
−4×3
Multiply the numbers
−12
(−3)2−(−12)
Rewrite the expression
32−(−12)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
32+12
Evaluate the power
9+12
Add the numbers
21
t=23±21
Separate the equation into 2 possible cases
t=23+21t=23−21
Substitute back
x2=23+21x2=23−21
Solve the equation for x
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Substitute back
x2=23+21
Take the root of both sides of the equation and remember to use both positive and negative roots
x=±23+21
Simplify the expression
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Evaluate
23+21
To take a root of a fraction,take the root of the numerator and denominator separately
23+21
Multiply by the Conjugate
2×23+21×2
Multiply the numbers
2×26+221
When a square root of an expression is multiplied by itself,the result is that expression
26+221
x=±26+221
Separate the equation into 2 possible cases
x=26+221x=−26+221
x=26+221x=−26+221x2=23−21
Solve the equation for x
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Substitute back
x2=23−21
Take the root of both sides of the equation and remember to use both positive and negative roots
x=±23−21
Simplify the expression
More Steps

Evaluate
23−21
Evaluate the power
221−3×−1
Evaluate the power
221−3×i
Evaluate the power
2221−6i
x=±2221−6i
Separate the equation into 2 possible cases
x=2221−6ix=−2221−6i
x=26+221x=−26+221x=2221−6ix=−2221−6i
Calculate
x=26+221x=−26+221
Solution
x1=−26+221,x2=26+221
Alternative Form
x1≈−1.947123,x2≈1.947123
Show Solution
