After evaluating the limit we get the answer as 3/5.
Given the expression is : limₓ₋₋₎₀ cos 2x ₋ cos 4x/1-cos2xcos4x
= limₓ₋₋₎₀ cos2x - (2cos²2x ₋ 1)/1-cos2x(2cos²2x - 1)
= limₓ₋₋₎₀ -2cos² + cos2x +1/₋2cos³2x + cos2x + 1
let u =cos2x that is, u → 0
= limu₋₋₎₁ -2u²+u+1/₋2u³+u+1
= limu₋₋₎₁ 2u + 1/2u²+2u+1
= 2+1/2×1² + 2 × 1 +1
= 3/2+2+1
= 3/5
hence we get the value as 3/5.
Learn more about Limits and continuity here:
brainly.com/question/12212916
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