Question
Simplify the expression
142x7−7x5
Evaluate
7x7−2x4x
Multiply the terms
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Multiply the terms
2x4x
Multiply the terms
2x4×x
Multiply the terms
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Evaluate
x4×x
Use the product rule an×am=an+m to simplify the expression
x4+1
Add the numbers
x5
2x5
7x7−2x5
Reduce fractions to a common denominator
7×2x7×2−2×7x5×7
Multiply the numbers
14x7×2−2×7x5×7
Multiply the numbers
14x7×2−14x5×7
Write all numerators above the common denominator
14x7×2−x5×7
Use the commutative property to reorder the terms
142x7−x5×7
Solution
142x7−7x5
Show Solution

Find the roots
x1=−214,x2=0,x3=214
Alternative Form
x1≈−1.870829,x2=0,x3≈1.870829
Evaluate
7x7−2x4x
To find the roots of the expression,set the expression equal to 0
7x7−2x4x=0
Multiply the terms
More Steps

Multiply the terms
2x4x
Multiply the terms
2x4×x
Multiply the terms
More Steps

Evaluate
x4×x
Use the product rule an×am=an+m to simplify the expression
x4+1
Add the numbers
x5
2x5
7x7−2x5=0
Subtract the terms
More Steps

Simplify
7x7−2x5
Reduce fractions to a common denominator
7×2x7×2−2×7x5×7
Multiply the numbers
14x7×2−2×7x5×7
Multiply the numbers
14x7×2−14x5×7
Write all numerators above the common denominator
14x7×2−x5×7
Use the commutative property to reorder the terms
142x7−x5×7
Use the commutative property to reorder the terms
142x7−7x5
142x7−7x5=0
Simplify
2x7−7x5=0
Factor the expression
x5(2x2−7)=0
Separate the equation into 2 possible cases
x5=02x2−7=0
The only way a power can be 0 is when the base equals 0
x=02x2−7=0
Solve the equation
More Steps

Evaluate
2x2−7=0
Move the constant to the right-hand side and change its sign
2x2=0+7
Removing 0 doesn't change the value,so remove it from the expression
2x2=7
Divide both sides
22x2=27
Divide the numbers
x2=27
Take the root of both sides of the equation and remember to use both positive and negative roots
x=±27
Simplify the expression
More Steps

Evaluate
27
To take a root of a fraction,take the root of the numerator and denominator separately
27
Multiply by the Conjugate
2×27×2
Multiply the numbers
2×214
When a square root of an expression is multiplied by itself,the result is that expression
214
x=±214
Separate the equation into 2 possible cases
x=214x=−214
x=0x=214x=−214
Solution
x1=−214,x2=0,x3=214
Alternative Form
x1≈−1.870829,x2=0,x3≈1.870829
Show Solution
