Question
Solve the inequality
Solve the inequality by testing the values in the interval
Solve the inequality by separating into cases
Solve for x
x∈(−∞,−8]∪[8,+∞)
Evaluate
x2(−x2−64)≤64(−x2−64)
Move the expression to the left side
x2(−x2−64)−64(−x2−64)≤0
Subtract the terms
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Evaluate
x2(−x2−64)−64(−x2−64)
Expand the expression
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Calculate
x2(−x2−64)
Apply the distributive property
x2(−x2)−x2×64
Multiply the terms
−x4−x2×64
Use the commutative property to reorder the terms
−x4−64x2
−x4−64x2−64(−x2−64)
Expand the expression
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Calculate
64(−x2−64)
Apply the distributive property
64(−x2)−64×64
Multiply the numbers
−64x2−64×64
Multiply the numbers
−64x2−4096
−x4−64x2−(−64x2−4096)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
−x4−64x2+64x2+4096
The sum of two opposites equals 0
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Evaluate
−64x2+64x2
Collect like terms
(−64+64)x2
Add the coefficients
0×x2
Calculate
0
−x4+0+4096
Remove 0
−x4+4096
−x4+4096≤0
Rewrite the expression
−x4+4096=0
Move the constant to the right-hand side and change its sign
−x4=0−4096
Removing 0 doesn't change the value,so remove it from the expression
−x4=−4096
Change the signs on both sides of the equation
x4=4096
Take the root of both sides of the equation and remember to use both positive and negative roots
x=±44096
Simplify the expression
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Evaluate
44096
Write the number in exponential form with the base of 8
484
Reduce the index of the radical and exponent with 4
8
x=±8
Separate the equation into 2 possible cases
x=8x=−8
Determine the test intervals using the critical values
x<−8−8<x<8x>8
Choose a value form each interval
x1=−9x2=0x3=9
To determine if x<−8 is the solution to the inequality,test if the chosen value x=−9 satisfies the initial inequality
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Evaluate
(−9)2(−(−9)2−64)≤64(−(−9)2−64)
Simplify
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Evaluate
(−9)2(−(−9)2−64)
Subtract the numbers
(−9)2(−145)
Evaluate the power
81(−145)
Multiply the numbers
−11745
−11745≤64(−(−9)2−64)
Simplify
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Evaluate
64(−(−9)2−64)
Subtract the numbers
64(−145)
Multiplying or dividing an odd number of negative terms equals a negative
−64×145
Multiply the numbers
−9280
−11745≤−9280
Check the inequality
true
x<−8 is the solutionx2=0x3=9
To determine if −8<x<8 is the solution to the inequality,test if the chosen value x=0 satisfies the initial inequality
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Evaluate
02×(−02−64)≤64(−02−64)
Simplify
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Evaluate
02×(−02−64)
Calculate
02×(−0−64)
Removing 0 doesn't change the value,so remove it from the expression
02×(−64)
Calculate
0×(−64)
Any expression multiplied by 0 equals 0
0
0≤64(−02−64)
Simplify
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Evaluate
64(−02−64)
Calculate
64(−0−64)
Removing 0 doesn't change the value,so remove it from the expression
64(−64)
Multiplying or dividing an odd number of negative terms equals a negative
−64×64
Multiply the numbers
−4096
0≤−4096
Check the inequality
false
x<−8 is the solution−8<x<8 is not a solutionx3=9
To determine if x>8 is the solution to the inequality,test if the chosen value x=9 satisfies the initial inequality
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Evaluate
92(−92−64)≤64(−92−64)
Simplify
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Evaluate
92(−92−64)
Subtract the numbers
92(−145)
Evaluate the power
81(−145)
Multiply the numbers
−11745
−11745≤64(−92−64)
Simplify
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Evaluate
64(−92−64)
Subtract the numbers
64(−145)
Multiplying or dividing an odd number of negative terms equals a negative
−64×145
Multiply the numbers
−9280
−11745≤−9280
Check the inequality
true
x<−8 is the solution−8<x<8 is not a solutionx>8 is the solution
The original inequality is a nonstrict inequality,so include the critical value in the solution
x≤−8 is the solutionx≥8 is the solution
Solution
x∈(−∞,−8]∪[8,+∞)
Show Solution
