Question
Solve the inequality
Solve the inequality by testing the values in the interval
Solve the inequality by separating into cases
x∈(−∞,−3)∪[0,307]∪(3,+∞)
Evaluate
x4−81log10(3)×(3x2×5)−log10(321)×(x×7)≥0
Find the domain
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Evaluate
x4−81=0
Move the constant to the right side
x4=81
Take the root of both sides of the equation and remember to use both positive and negative roots
x=±481
Simplify the expression
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Evaluate
481
Write the number in exponential form with the base of 3
434
Reduce the index of the radical and exponent with 4
3
x=±3
Separate the inequality into 2 possible cases
{x=3x=−3
Find the intersection
x∈(−∞,−3)∪(−3,3)∪(3,+∞)
x4−81log10(3)×(3x2×5)−log10(321)×(x×7)≥0,x∈(−∞,−3)∪(−3,3)∪(3,+∞)
Remove the parentheses
x4−81log10(3)×3x2×5−log10(321)×x×7≥0
Simplify
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Evaluate
x4−81log10(3)×3x2×5−log10(321)×x×7
Simplify
x4−81log10(3)×3x2×5−21log10(3)×x×7
Multiply
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Multiply the terms
log10(3)×3x2×5
Multiply the terms
log10(3)×15x2
Use the commutative property to reorder the terms
15log10(3)×x2
x4−8115log10(3)×x2−21log10(3)×x×7
Multiply
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Multiply the terms
21log10(3)×x×7
Multiply the numbers
27log10(3)×x
Multiply the numbers
27log10(3)x
x4−8115log10(3)×x2−27log10(3)x
Rewrite the expression
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Evaluate
15log10(3)×x2−27log10(3)x
Rewrite the expression
15log10(3)×x2−27log10(3)×x
Reduce fractions to a common denominator
215log10(3)×x2×2−27log10(3)×x
Write all numerators above the common denominator
215log10(3)×x2×2−7log10(3)×x
Multiply the terms
230log10(3)×x2−7log10(3)×x
x4−81230log10(3)×x2−7log10(3)×x
Multiply by the reciprocal
230log10(3)×x2−7log10(3)×x×x4−811
Multiply the terms
2(x4−81)30log10(3)×x2−7log10(3)×x
2(x4−81)30log10(3)×x2−7log10(3)×x≥0
Set the numerator and denominator of 2(x4−81)30log10(3)×x2−7log10(3)×x equal to 0 to find the values of x where sign changes may occur
30log10(3)×x2−7log10(3)×x=02(x4−81)=0
Calculate
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Evaluate
30log10(3)×x2−7log10(3)×x=0
Factor the expression
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Evaluate
30log10(3)×x2−7log10(3)×x
Rewrite the expression
log10(3)×x×30x−log10(3)×x×7
Factor out log10(3)×x from the expression
log10(3)×x(30x−7)
log10(3)×x(30x−7)=0
When the product of factors equals 0,at least one factor is 0
log10(3)×x=030x−7=0
Solve the equation for x
x=030x−7=0
Solve the equation for x
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Evaluate
30x−7=0
Move the constant to the right-hand side and change its sign
30x=0+7
Removing 0 doesn't change the value,so remove it from the expression
30x=7
Divide both sides
3030x=307
Divide the numbers
x=307
x=0x=307
x=0x=3072(x4−81)=0
Calculate
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Evaluate
2(x4−81)=0
Rewrite the expression
x4−81=0
Move the constant to the right side
x4=81
Take the root of both sides of the equation and remember to use both positive and negative roots
x=±481
Simplify the expression
More Steps

Evaluate
481
Write the number in exponential form with the base of 3
434
Reduce the index of the radical and exponent with 4
3
x=±3
Separate the equation into 2 possible cases
x=3x=−3
x=0x=307x=3x=−3
Determine the test intervals using the critical values
x<−3−3<x<00<x<307307<x<3x>3
Choose a value form each interval
x1=−4x2=−2x3=607x4=2x5=4
To determine if x<−3 is the solution to the inequality,test if the chosen value x=−4 satisfies the initial inequality
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Evaluate
2((−4)4−81)30log10(3)×(−4)2−7log10(3)×(−4)≥0
Simplify
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Evaluate
2((−4)4−81)30log10(3)×(−4)2−7log10(3)×(−4)
Subtract the numbers
2×17530log10(3)×(−4)2−7log10(3)×(−4)
Multiply the terms
2×175480log10(3)−7log10(3)×(−4)
Multiply the numbers
2×175480log10(3)−(−28log10(3))
Multiply the numbers
350480log10(3)−(−28log10(3))
Subtract the terms
350508log10(3)
Cancel out the common factor 2
175254log10(3)
175254log10(3)≥0
Calculate
0.692507≥0
Check the inequality
true
x<−3 is the solutionx2=−2x3=607x4=2x5=4
To determine if −3<x<0 is the solution to the inequality,test if the chosen value x=−2 satisfies the initial inequality
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Evaluate
2((−2)4−81)30log10(3)×(−2)2−7log10(3)×(−2)≥0
Simplify
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Evaluate
2((−2)4−81)30log10(3)×(−2)2−7log10(3)×(−2)
Subtract the numbers
2(−65)30log10(3)×(−2)2−7log10(3)×(−2)
Multiply the terms
2(−65)120log10(3)−7log10(3)×(−2)
Multiply the numbers
2(−65)120log10(3)−(−14log10(3))
Multiply the numbers
−130120log10(3)−(−14log10(3))
Subtract the terms
−130134log10(3)
Cancel out the common factor 2
−6567log10(3)
Use b−a=−ba=−ba to rewrite the fraction
−6567log10(3)
−6567log10(3)≥0
Calculate
−0.491802≥0
Check the inequality
false
x<−3 is the solution−3<x<0 is not a solutionx3=607x4=2x5=4
To determine if 0<x<307 is the solution to the inequality,test if the chosen value x=607 satisfies the initial inequality
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Evaluate
2((607)4−81)30log10(3)×(607)2−7log10(3)×607≥0
Simplify
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Evaluate
2((607)4−81)30log10(3)×(607)2−7log10(3)×607
Subtract the numbers
2×6042401−180430log10(3)×(607)2−7log10(3)×607
Multiply the numbers
2×6042401−180412049log10(3)−7log10(3)×607
Multiply the numbers
2×6042401−180412049log10(3)−6049log10(3)
Multiply the numbers
64800002401−180412049log10(3)−6049log10(3)
Subtract the numbers
64800002401−1804−12049log10(3)
Multiply by the reciprocal
−12049log10(3)×2401−18046480000
Reduce the numbers
−49log10(3)×2401−180454000
Multiply the numbers
−2401−180449log10(3)×54000
Multiply the numbers
−2401−18042646000log10(3)
−2401−18042646000log10(3)≥0
Calculate
0.001203≥0
Check the inequality
true
x<−3 is the solution−3<x<0 is not a solution0<x<307 is the solutionx4=2x5=4
To determine if 307<x<3 is the solution to the inequality,test if the chosen value x=2 satisfies the initial inequality
More Steps

Evaluate
2(24−81)30log10(3)×22−7log10(3)×2≥0
Simplify
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Evaluate
2(24−81)30log10(3)×22−7log10(3)×2
Subtract the numbers
2(−65)30log10(3)×22−7log10(3)×2
Multiply the terms
2(−65)120log10(3)−7log10(3)×2
Multiply the terms
2(−65)120log10(3)−14log10(3)
Multiply the numbers
−130120log10(3)−14log10(3)
Subtract the numbers
−130106log10(3)
Cancel out the common factor 2
−6553log10(3)
Use b−a=−ba=−ba to rewrite the fraction
−6553log10(3)
−6553log10(3)≥0
Calculate
−0.389037≥0
Check the inequality
false
x<−3 is the solution−3<x<0 is not a solution0<x<307 is the solution307<x<3 is not a solutionx5=4
To determine if x>3 is the solution to the inequality,test if the chosen value x=4 satisfies the initial inequality
More Steps

Evaluate
2(44−81)30log10(3)×42−7log10(3)×4≥0
Simplify
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Evaluate
2(44−81)30log10(3)×42−7log10(3)×4
Subtract the numbers
2×17530log10(3)×42−7log10(3)×4
Multiply the terms
2×175480log10(3)−7log10(3)×4
Multiply the terms
2×175480log10(3)−28log10(3)
Multiply the numbers
350480log10(3)−28log10(3)
Subtract the numbers
350452log10(3)
Cancel out the common factor 2
175226log10(3)
175226log10(3)≥0
Calculate
0.616168≥0
Check the inequality
true
x<−3 is the solution−3<x<0 is not a solution0<x<307 is the solution307<x<3 is not a solutionx>3 is the solution
The original inequality is a nonstrict inequality,so include the critical value in the solution
x<−3 is the solution0≤x≤307 is the solutionx>3 is the solution
The final solution of the original inequality is x∈(−∞,−3)∪[0,307]∪(3,+∞)
x∈(−∞,−3)∪[0,307]∪(3,+∞)
Check if the solution is in the defined range
x∈(−∞,−3)∪[0,307]∪(3,+∞),x∈(−∞,−3)∪(−3,3)∪(3,+∞)
Solution
x∈(−∞,−3)∪[0,307]∪(3,+∞)
Show Solution
