Question

explain ( 5-1 + 7-1 )-1 as a rational number​

Answer 1

Answer:

We know that,

=(5)

−1

=(1/5)

1

...[∵(a/b)

−n

=(b/a)

n

]

=(7)

−1

=(1/7)

1

...[∵(a/b)

−n

=(b/a)

n

]

Now subtract,

={(1/5)−(1/7)}

−1

={(7−5)/35}

−1

...[LCM of 5 and 7 is 35]

={2/35}

−1

={35/2}