Ravi states: 'For any two rationals a and b, a x b = b x a, but a - b is not equal to b - a unless a = b.' For a = 5/6 and b = 5/6, what is a - b, and does this special case make subtraction commutative in general?

Question

Accepted Answer

a - b = 0; no, equality only happens when a = b, not in general. 5/6 - 5/6 = 0 and 5/6 - 5/6 = 0, so they are equal here only because a = b. In general a - b is not b - a, so subtraction is not commutative.

Ravi states: 'For any two rationals a and $b$ , a $x b = b x$ a, but $a - b$ is not equal to $b - a$ unless $a = b$ .'
For $a = \frac{5}{6}$ and $b = \frac{5}{6}$ , what is $a - b$ , and does this special case make subtraction commutative in general?

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More Class 8 Properties of Rational Numbers practice

Ravi states: 'For any two rationals a and b, a xb=bx a, but a−b is not equal to b−a unless a=b.'For a=65​ and b=65​, what is a−b, and does this special case make subtraction commutative in general?

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 8 Properties of Rational Numbers practice

Ravi states: 'For any two rationals a and $b$ , a $x b = b x$ a, but $a - b$ is not equal to $b - a$ unless $a = b$ .'
For $a = \frac{5}{6}$ and $b = \frac{5}{6}$ , what is $a - b$ , and does this special case make subtraction commutative in general?