Sharp EL-9900 - Manual (Page 87)

12
Advanced Keyboard/CALCULUS USING THE SHARP EL-9900
Copyright © 2002, Sharp Electronics Corporation. Permission is granted to photocopy for educational use only.
1. Calculate and draw a graph of the area of the region between
f(x) = 5x – x 2 + 12 and g(x) = e x + 5.
2. Return to and clear the Y prompts by pressing Y= CL . Clear additional
prompts if necessary.
3. Input f(x) in Y1 with the keystrokes 5 X/
θ/T/n – X/θ/T/n x 2 + 1
2 ENTER . Input g(x) in Y2 with the keystrokes 2ndF e x X/
θ/T/n
+ 5 .
4. Enter the viewing window -5 < x < 5 and -5 < y < 20. Your viewing window
should clearly show the region between f(x) and g(x) and, if applicable,
display the intersections of the functions. Press GRAPH to view the graphs.
5. Shade the region between the two curves by pressing 2ndF DRAW
G (SHADE) 1 (SET). Since Y2 is the function "on the bottom," press
2ndF VARS ENTER A (EQVARS) ENTER 2 (Y2) and since Y1 is the
function “on the top," press 2ndF VARS ENTER 1 (Y1). Press GRAPH
to view the shaded region.
6. Next, find the limits of integration. Press 2ndF CALC 2 (Intsct). Do this
twice to obtain the x-coordinates of the two points of intersection. The
points of intersection are x = -1.09 and x = 2.58.
7. Find the approximate area by pressing CL MATH A (CALC) 0 6
(
∫ ) enter -1.09, press ▲ , enter 2.58, press , enter the function
“on the top,” 5x – x 2 + 12, press – ( , enter the function “on the bottom,”
e x + 5, press ) MATH 0 7 (dx). Press ENTER to obtain the approximate
area of 20.34.
AREA BETWEEN CURVES
▼
▼
Ч
+ –
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