Section 3: Functions47
Sample Case: Reciprocals. Calculate: ¼=.25.
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4 g1/x  
  0.25
  Reciprocal of 4.
Naturally, you can use this value in another calculation. For example, to go on and calculate
  1  ,
 
  1/4 + 1/3
¼ is already calculated. We need only
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  0.24
  Reciprocal of 4.
3 g1/x  
  0.33
  Reciprocal of 3.
+   
  0.58
  Sum of reciprocals.
g1/x   
  1.71
  Answer reciprocal of sum.
Sample Case: Factorial. Calculate the number of ways 6 people can line up for a photograph.
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6 gn!  
  720.00
  Answer.
Sample Case: Exponential. In the preceding section we calculated the successive terms of a geometric series to find that after 6 periods, $1000 invested at 10% grows to $1771.56. Using the gyX function, the same result is obtained by evaluating the following:
1000 (1.10)6
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1000 ENTER   
  1000.00
  Original amount
1.10 ENTER  6 gyX  
  1.77
  (1.10)6
×   
  1771.56
  Answer.