Question 190750
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*[tex \LARGE \ \ \ \ \ \ \ \ \ \  a^2 - b^2 = (a + b)(a - b)]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ 81x^2 = (9x)^2]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ 121 = 11^2]



John
*[tex \LARGE e^{i\pi} + 1 = 0]
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