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a * b = ab/a+b for all a, b that satisfy a is different from
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19 Jul 2019, 09:32
19 Jul 2019, 09:32
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8% (00:28) wrong based on 89 sessions
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\(a \circ b = \frac{ab}{a+b}\) for all a, b that satisfy \(a ≠ -b\). What is the value of \((–4) \circ 2\)?
A. \(-4\)
B. \(-2\)
C. \(-\frac{4}{3}\)
D. \(\frac{4}{3}\)
E. \(4\)
A. \(-4\)
B. \(-2\)
C. \(-\frac{4}{3}\)
D. \(\frac{4}{3}\)
E. \(4\)
Re: a * b = ab/a+b for all a, b that satisfy a is different from
[#permalink]
20 Sep 2019, 14:41
20 Sep 2019, 14:41
1
(-4)°2= ((-4)(2))/(-4+2)= (-8)/(-2)=4
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Re: a * b = ab/a+b for all a, b that satisfy a is different from
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07 Aug 2022, 23:27
07 Aug 2022, 23:27
1
Given that \(a \circ b = \frac{ab}{a+b}\) and we need to find the value of \((–4) \circ 2\)
To find \((–4) \circ 2\) we need to compare what is before and after \(\circ\) in \((–4) \circ 2\) and \(a \circ b\)
=> We need to substitute a with -4 and b with 2 in \(a \circ b = \frac{ab}{a+b}[/m to get the value of [m](–4) \circ 2\)
=> \(-4 \circ 2 = \frac{-4*2}{-4+2}\) = \(\frac{-8}{-2}\) = 4
So, Answer will be E
Hope it helps!
Watch the following video to learn the Basics of Functions and Custom Characters
To find \((–4) \circ 2\) we need to compare what is before and after \(\circ\) in \((–4) \circ 2\) and \(a \circ b\)
=> We need to substitute a with -4 and b with 2 in \(a \circ b = \frac{ab}{a+b}[/m to get the value of [m](–4) \circ 2\)
=> \(-4 \circ 2 = \frac{-4*2}{-4+2}\) = \(\frac{-8}{-2}\) = 4
So, Answer will be E
Hope it helps!
Watch the following video to learn the Basics of Functions and Custom Characters
