If r☉s = rs + r + s, then for what value of s is r ☉s equal to r for all values of r?
(A) –1 (B) 0 (C) 1
(D) (E) r
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amitdgr
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The question asks -> For what value of s, rs + r + s will be = rIf r☉s = rs + r + s, then for what value of s is r ☉s equal to r for all values of r?
we can clearly see, When s=0 => rs + r + s =r
Otherwise, plug in the answer choices in the above equation and see for which choice we satisfy the equation rs + r + s=r
Is the OA B) 0 ?
Amit
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parallel_chase
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smclean23 wrote:If r☉s = rs + r + s, then for what value of s is r ☉s equal to r for all values of r?
(A) –1 (B) 0 (C) 1
(D) (E) r
r☉s = rs + r + s =>
r☉s = s(r+1) + r
Therefore only value of S for r☉s = r is 0.
Hence answer B.
What is OA?
