Sharp El-5020 User Manual

							
Sharp EL-5020 
Executing the program: 
Example: 
Given that the lengths of ∆ABC are 30, 40 and 50, find the area of ∆ABC. 
Procedure Display Remark 
1.  MODE   0   DEG mode 
2.  2ndF   _   Execute program 1: 
3.  3   0   =  
 4   0   =  
 5   0   =  
600 Area of ∆ABC 
Note: Pressing  =  after the last procedure allows the program to be executed again. 
 
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Sharp EL-5020 
Centre and Radius of a Circle 
Given the equation of a circle Ax2 + Ay2 + Dx + Ey + F = 0, 
centre of the circle is )2,2(A
E
A
D−−, 
radius of the circle A
F
A
E
A
D−+=22)2()2(. 
 
When the equation of a circle is given, this program can be used to find the centre and the radius of 
the circle. 
 
Storing the program: 
Step 1 2 3 4 5 6 7 
Key  MODE   1   2ndF  _   2ndF  ON/C   =  
 
Step 8 9 10 11 12 13 14 
Key  +/-   2  A  STO   MODE  2ndF   x2  
 
Step 15 16 17 18 19 20 21 
Key B  STO   hyp  C  ÷  A  STO  
 
Step 22 23 24 25 26 27 28 
Key  sin  B ， C ，  √   (  
 
Step 29 30 31 32 33 34 35 
Key B  x2   +  C  x2   +   2  
 
Step 36 37 38 39 40 41 42 
Key D  ÷  A  )   STO   cos   MODE 
 
Step 43       
Key  0        
 
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Sharp EL-5020 
Executing the program: 
Examples: 
(a) Find the centre and the radius of circle x2 + y2 + 6x − 4y + 9 = 0. 
Procedure Display Remark 
1.  MODE   0   DEG mode 
2.  2ndF   _   Execute program 1: 
3.  1   =   Coefficient of x2 and y2
4.  6   =  
 4   +/-   =  
-3 x-coordinate of centre 
5.  =  2 y-coordinate of centre 
6.  =  
 9   =  
2 radius 
Note: Pressing  =  after the last procedure allows the program to be executed again. 
 
(b) Find the centre and the radius of circle 2x2 + 2y2 + 4x − 8y + 25 = 0. 
Procedure Display Remark 
1.  MODE   0   DEG mode 
2.  2ndF   _   Execute program 1: 
3.  2   =   Coefficient of x2 and y2
4.  4   =  
 8   +/-   =  
-1 x-coordinate of centre 
5.  =  2 y-coordinate of centre 
6.  =  
 2   5   =  
Er2 An imaginary circle 
Note: Press  ON/C  to exit the program. 
 
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Sharp EL-5020 
Quadratic Formula 
For the quadratic equation ax2 + bx + c = 0, 
a
acbbx2
42−±−= 
 
This program is used to solve quadratic equations with real roots. 
 
Storing the program: 
Step 1 2 3 4 5 6 7 
Key  MODE   1   2ndF  _   2ndF  ON/C   =  
 
Step 8 9 10 11 12 13 14 
Key A 9 B  x2   -   4  A 
 
Step 15 16 17 18 19 20 21 
Key C  STO   cos   √  D  -  B 
 
Step 22 23 24 25 26 27 28 
Key  )   ÷   2  A  STO   tan  ， 
 
Step 29 30 31 32 33 34 35 
Key  +/-  E  -  B  ÷  A  STO  
 
Step 36 37 38     
Key  xPOL   MODE   0      
 
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Sharp EL-5020 
Executing the program: 
Examples: 
(a) Solve x2 + 2x − 3 = 0. 
Procedure Display Remark 
1.  MODE   0   DEG mode 
2.  2ndF   _   Execute program 1: 
3.  1   =  
 2   =  
 3   +/-   =  
1 First root 
4.  =  -3 Second root 
Note: Pressing  =  after the last procedure allows the program to be executed again. 
 
(b) Solve 2x2 + 3x + 4 = 0. 
Procedure Display Remark 
1.  MODE   0   DEG mode 
2.  2ndF   _   Execute program 1: 
3.  2   =  
 3   =  
 4   =  
Er2 No real roots 
Note: Press  ON/C  to exit the program. 
 
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Sharp EL-5020 
Mean and Standard Deviation (build-in function) 
This function is used to find the mean and the standard deviation of a set of data. 
 
Example: 
Given a set of data: 45, 47, 48, 48, 48, 49, 52, 53, 60, find the mean and the standard deviation of 
the data. 
Procedure Display Remark 
1.  MODE   3   STAT 1 mode 
2.  2ndF   ON/C   Clear all data in memory 
3.  4   5   )  
 4   7   )  
 4   8   )  
 4   8   )  
 4   8   )  
 4   9   )  
 5   2   )  
 5   3   )  
 6   0   )  
 Input the data 
4.  RCL   4  50 Arithmetic mean 
5.  RCL   6  4.216370214 Standard deviation 
6.  RCL   0  9 Number of data 
7.  RCL   y  450 Sum of data 
Note: To add a new datum, do not press  2ndF   ON/C  or else all data input will be 
cleared. 
 
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