This Lesson (Do not fall into a TRAP when analyzing problems on trigonometric functions) was created by by ikleyn(52781): View Source, Show About ikleyn:
Do not fall into a TRAP when analyzing problems on trigonometric functions
Problem 1
Describe what the graph of f(x) = would look like?
Address all numerical elements and their effects on the parent function.
Solution
Given function f(x) = is IDENTICAL to / (is the same as)
f(x) = .
The parent function is a(x) = sin(x).
Amplitude of f(x) is 1.
Period of f(x) is .
Phase shift of f(x) is 0 (zero).
Vertical shift is -2 (2 units down).
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This problem is a TRAP : it has a huge underwater stone for unexperienced reader.
The sign "-" (minus) before sine and the shift by in the argument
mutually annihilate each other, so the final function, actually, has no shift (!)
The meaning of the problem is to teach a reader recognizing
such traps to avoid falling into them in the future.