x2 - (2x)2 = x2 - 4x2 = -3x2 x2 - 2x2 = -x2
(x2 + 1)(x2 - 2)
1 over x2 - 4 is the multiplicative inverse of x2 minus four 1/x2 - 4
y squared-y-72 is an algebraic expression because it does not contain an equality sign.
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The factoring is as follows: x2 - y2 = (x + y) * (x - y)
(x - y)2 = x2 - 2xy + y2
(x - y)(x + y)
x2 - (2x)2 = x2 - 4x2 = -3x2 x2 - 2x2 = -x2
x^3 - 121x
-x2+2x
You must use the difference of squares formula: x2 - y2 = (x + y)(x - y) Thus: x2 - 25 = (x + 5)(x - 5).
(x2 + 1)(x2 - 2)
1 over x2 - 4 is the multiplicative inverse of x2 minus four 1/x2 - 4
y squared-y-72 is an algebraic expression because it does not contain an equality sign.
-- The number that (x2-y2) represents depends on the values of 'x' and 'y', which you haven't seen fit to include. -- When (x2-y2) is factored, it can be represented as [ (x+y) times (x-y) ], which is often easier to evaluate, or integrate, or differentiate, than the original expression is. But you still need to know the values of 'x' and 'y'.
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