The value of (x - y)(x + y) + (y - z)(y + z) + (z - x)(z + x) is:
0
The question asks for the value of the expression: \((x - y)(x + y) + (y - z)(y + z) + (z - x)(z + x)\) To solve this, we can use a fundamental algebraic identity known as the 'difference of squares'.
The difference of squares identity states that for any two terms 'a' and 'b': \(a^2 - b^2 = (a - b)(a + b)\) We can apply this identity to each part of the given expression:
Now, we substitute these results back into the original expression:
\( (x^2 - y^2) + (y^2 - z^2) + (z^2 - x^2) \)Let's rearrange the terms to group the like terms together:
\( x^2 - x^2 + y^2 - y^2 + z^2 - z^2 \)Now, we can perform the subtraction for each pair of like terms:
Adding these results together:
\( 0 + 0 + 0 = 0 \)Therefore, the value of the expression \((x - y)(x + y) + (y - z)(y + z) + (z - x)(z + x)\) is 0.
By applying the difference of squares identity and simplifying the terms, we find that the entire expression evaluates to 0.
Reduce to linear form
\(\frac{5x + 1}{2x} = \frac{5}{4}\)
What is the product of (x + a) and (x + b)?
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A fraction becomes \(1\over2\) if 2 is added to the numerator and 5 is added to the denominator. It also becomes \(1\over 3\) if 2 is subtracted from both the numerator and denominator. The positive difference between the numerator and the denominator is:
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