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Prove that (a − b) × (a b) = 2(a × b).

User Sra
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Final answer:

To prove that (a - b) x (a + b) = 2(a x b), we use the distributive property of multiplication and simplify both sides of the equation.

Step-by-step explanation:

To prove that (a - b) x (a + b) = 2(a x b), we can expand both sides using the distributive property of multiplication.

Expanding the left side, we get (a - b)(a + b) = a(a + b) - b(a + b).

Simplifying further, we have a^2 + ab - ab - b^2 = a^2 - b^2.

On the right side, we have 2(a x b), which represents the scalar projection of the vector a onto the vector b multiplied by the magnitude of b.

Since a^2 - b^2 is equal to the scalar projection of a onto b multiplied by the magnitude of b, we can conclude that (a - b)(a + b) = 2(a x b).

User Rudensm
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