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Algebra/Binary... Operation

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Question
Mathematics is my favorite subject, but the following question makes me feel that mathematics is pointles and grey:
A binary operation * is defined on the set R of real numbers by a * b= a + b + ab whare a, b belongs to R
(i) calculate 5*(-2)*5
(ii) find the identity element of R under the operation *
(* symbolizes binary operation; that is how it is used in my book.)
HELP ME SOLVE IT!

Answer
Since a * b = a + b + ab, this says we only take two numbers at once.
Since the 1st two numbers are 5 and -2, take a=5 and b=-2.
This gives a*b = 5 -2 -10 = 3-10= -7.

We then use -7 and 5 as a and b.
This says that -7 * 5 = -7 + 5 - 35. = -37.

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Scott A Wilson

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Any algebraic question you've got. That includes question that are linear, quadratic, exponential, etc.

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I have solved story problems, linear equations, parabolic equations. I have also solved some 3rd order equations and equations with multiple variables.

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Documents at Boeing in assistance on the manufacturiing floor.

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MS at math OSU in mathematics at OSU, 1986. BS at OSU in mathematical sciences (math, statistics, computer science), 1984.

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Both my BS and MS degrees were given with honors.

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