SOLUTION: Evaluate: (a+b)^2

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Question 176959This question is from textbook
: Evaluate: (a+b)^2 This question is from textbook

Found 2 solutions by jim_thompson5910, dini:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

%28a%2Bb%29%5E2 Start with the given expression.


%28a%2Bb%29%28a%2Bb%29 Expand. Remember something like x%5E2=x%2Ax.


Now let's FOIL the expression.


Remember, when you FOIL an expression, you follow this procedure:


%28highlight%28a%29%2Bb%29%28highlight%28a%29%2Bb%29 Multiply the First terms:%28a%29%2A%28a%29=a%5E2.


%28highlight%28a%29%2Bb%29%28a%2Bhighlight%28b%29%29 Multiply the Outer terms:%28a%29%2A%28b%29=a%2Ab.


%28a%2Bhighlight%28b%29%29%28highlight%28a%29%2Bb%29 Multiply the Inner terms:%28b%29%2A%28a%29=a%2Ab.


%28a%2Bhighlight%28b%29%29%28a%2Bhighlight%28b%29%29 Multiply the Last terms:%28b%29%2A%28b%29=b%5E2.


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a%5E2%2Ba%2Ab%2Ba%2Ab%2Bb%5E2 Now collect every term to make a single expression.


a%5E2%2B2%2Aa%2Ab%2Bb%5E2 Now combine like terms.


So %28a%2Bb%29%5E2 FOILs to a%5E2%2B2%2Aa%2Ab%2Bb%5E2.


In other words, %28a%2Bb%29%5E2=a%5E2%2B2%2Aa%2Ab%2Bb%5E2.

Answer by dini(5) About Me  (Show Source):
You can put this solution on YOUR website!
(a+b)*(a+b)
=a^2+ab+ab+b^2
=a^2+2(ab)+b^2