Casio fx-570MS - Manual (Page 15)

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Trigonometric Function Addition Theorem
Determine the validity of: sin75
°
= sin (30
° + 45°) = sin30° cos45° + cos30° sin45.
sin Function Addition Theorem:
sin(
α + β) = sinα cosβ + cosα sinβ
1 .
Enter the COMP Mode.
F 1
2 .
Press the F key a number of times until degrees (Deg) are specified as the angle unit.
F • • • 1 (Deg)
]
3 .
Determine value of sin75
°.
S 75 =
Result: sin75
° = 0.965925826
4 .
Determine value of sin30
° cos45° + cos30° sin45°.
S 30 - W 45 + W 30 - S 45 =
Result: sin30
° cos45° + cos30° sin45° = 0.965925826
5 .
Use the [ key to display the result obtained in step 3 to see if it matches the values obtained in
step 4.
Example Example
Explanation Explanation
Operation