Question 925477:  Use Pascal's triangle to expand the expression. 
(x + y)^8 
 Answer by MathLover1(20850)      (Show Source): 
You can  put this solution on YOUR website! Use Pascal's Triangle to expand each binomial. 
 
 
ANSWER:
 
Pascal's Triangle. 
 
It is a triangle of numbers,  which is given below:
 
 
1 
1 1 
1 2 1 
1 3 3 1 
1 4 6 4 1 
1 5 10 10 5 1 
1 6 15 20 15 6 1 
1 7 21 35 35 21 7 1 
1 8 28 56 70 56 28 8 1 
1 9 36 84 126 126 84 36 9 1 
1 10 45 120 210 252 210 120 45 10 1
 
 
Each number in the triangle is the sum of two above. For example, the 6 on line 5 is the sum of the pair of 3's above. So the next line is
 
1, 10 (1 + 9), 45 (9 + 36), 120 (36 + 84), etc.
 
 
Study these numbers and see if you can figure what the next line should be before reading on . . .
 
Your question.
 
 
 
 
Nineth raw of the triangle gives,COEFFIECIENTS OF THE EXPANSION.
 
That is,  
         
 
And the variable terms  will come like this,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 )
 
Since here it is  , the sign of the all  terms will be   positive,
 
 
 
 
 
 
 
which is the  answer to your question 
 
 
 
 
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