Calculated Industries 4090 - Manual (Page 45)

44 — ITI S
HEET
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/HVAC P
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Trig Examples (Cont’d)
Example 3 — Tan A:
Find the length of the transition for a 20° angle:
Side a = 18 Inches
Side b = unknown
a) Longhand Method: Use Tan = Opposite/Adjacent
KEYSTROKE DISPLAY
1. First solve for Tan 20° to find ratio, then enter in Memory:
o o 0.
2 0 t μ M+ 0.36397
2. Solve for Side b by dividing Side a by stored ratio:
1 8 ÷ ® μ = 49.45459
(49.5 inches)
3. Clear Memory and clear display:
® ® o 0.
b) Use Pythagorean Theorem Keys:
KEYSTROKE DISPLAY
o o 0.
1 8 r Y 18.
2 0 p /_ Ø 20.°
R X 49.45459
(49.5 inches)
M
M