Determine Approach: Determine the approach to factor 16x8−1. This expression is a difference of squares because it can be written as (4x4)2−12.
Apply Formula: Apply the difference of squares formula.The difference of squares formula is a2−b2=(a−b)(a+b). Here, a=4x4 and b=1.So, 16x8−1=(4x4)2−12=(4x4−1)(4x4+1).
Check Further Factoring: Check if further factoring is possible.The term 4x4+1 cannot be factored further as it is not a difference of squares. However, 4x4−1 is a difference of squares since it can be written as (2x2)2−12.
Factor Further: Factor 4x4−1 further using the difference of squares formula.We have (2x2)2−12=(2x2−1)(2x2+1).
Check Factoring: Check if further factoring is possible for the new terms.The term 2x2+1 cannot be factored further as it is not a difference of squares. The term 2x2−1 is also a difference of squares since it can be written as (x2)2−12.
Factor Further: Factor 2x2−1 further using the difference of squares formula.We have (x2)2−12=(x2−1)(x2+1).
Combine Factored Terms: Combine all the factored terms to get the final factored form.The fully factored form of 16x8−1 is (4x4+1)(2x2−1)(2x2+1)=(4x4+1)(x2−1)(x2+1).
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