Evaluate
2x\left(x-2\right)
Expand
2x^{2}-4x
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x^{2}-4x+4+\left(x+2\right)\left(x-2\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x^{2}-4x+4+x^{2}-4
Consider \left(x+2\right)\left(x-2\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 2.
2x^{2}-4x+4-4
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}-4x
Subtract 4 from 4 to get 0.
x^{2}-4x+4+\left(x+2\right)\left(x-2\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x^{2}-4x+4+x^{2}-4
Consider \left(x+2\right)\left(x-2\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 2.
2x^{2}-4x+4-4
Combine x^{2} and x^{2} to get 2x^{2}.
2x^{2}-4x
Subtract 4 from 4 to get 0.
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Limits
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