Question
Simplify the expression
−2x2−84x4
Evaluate
3x2−7x2×12x2−5x2
Multiply
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Multiply the terms
−7x2×12x2
Multiply the terms
−84x2×x2
Multiply the terms with the same base by adding their exponents
−84x2+2
Add the numbers
−84x4
3x2−84x4−5x2
Solution
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Evaluate
3x2−5x2
Collect like terms by calculating the sum or difference of their coefficients
(3−5)x2
Subtract the numbers
−2x2
−2x2−84x4
Show Solution

Factor the expression
−2x2(1+42x2)
Evaluate
3x2−7x2×12x2−5x2
Multiply
More Steps

Multiply the terms
7x2×12x2
Multiply the terms
84x2×x2
Multiply the terms with the same base by adding their exponents
84x2+2
Add the numbers
84x4
3x2−84x4−5x2
Subtract the terms
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Evaluate
3x2−5x2
Collect like terms by calculating the sum or difference of their coefficients
(3−5)x2
Subtract the numbers
−2x2
−2x2−84x4
Rewrite the expression
−2x2−2x2×42x2
Solution
−2x2(1+42x2)
Show Solution

Find the roots
x1=−4242i,x2=4242i,x3=0
Alternative Form
x1≈−0.154303i,x2≈0.154303i,x3=0
Evaluate
3x2−7x2×12x2−5x2
To find the roots of the expression,set the expression equal to 0
3x2−7x2×12x2−5x2=0
Multiply
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Multiply the terms
7x2×12x2
Multiply the terms
84x2×x2
Multiply the terms with the same base by adding their exponents
84x2+2
Add the numbers
84x4
3x2−84x4−5x2=0
Subtract the terms
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Simplify
3x2−84x4−5x2
Subtract the terms
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Evaluate
3x2−5x2
Collect like terms by calculating the sum or difference of their coefficients
(3−5)x2
Subtract the numbers
−2x2
−2x2−84x4
−2x2−84x4=0
Factor the expression
−2x2(1+42x2)=0
Divide both sides
x2(1+42x2)=0
Separate the equation into 2 possible cases
x2=01+42x2=0
The only way a power can be 0 is when the base equals 0
x=01+42x2=0
Solve the equation
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Evaluate
1+42x2=0
Move the constant to the right-hand side and change its sign
42x2=0−1
Removing 0 doesn't change the value,so remove it from the expression
42x2=−1
Divide both sides
4242x2=42−1
Divide the numbers
x2=42−1
Use b−a=−ba=−ba to rewrite the fraction
x2=−421
Take the root of both sides of the equation and remember to use both positive and negative roots
x=±−421
Simplify the expression
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Evaluate
−421
Evaluate the power
421×−1
Evaluate the power
421×i
Evaluate the power
4242i
x=±4242i
Separate the equation into 2 possible cases
x=4242ix=−4242i
x=0x=4242ix=−4242i
Solution
x1=−4242i,x2=4242i,x3=0
Alternative Form
x1≈−0.154303i,x2≈0.154303i,x3=0
Show Solution
