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fr33pl4gu3
Aug20-08, 02:16 PM
f(x) = 9 sin 7 x, and g(x) = 18 sin(7 x + 5)

so, i assume by looking just like this g(x) is twice much more than f(x) and 5 units more, correct??

NoMoreExams
Aug20-08, 02:22 PM
What do you mean by twice much more and 5 units more? You need to figure out what each of the factors in f(x) = A*sin(Bx + C) + D does, for example, A is the amplitude, 2pi/B is the period, now think as to what C and D are.

fr33pl4gu3
Aug20-08, 02:52 PM
Thanks.

Redbelly98
Aug20-08, 04:00 PM
If you're wondering how much the g(x) is shifted relative to f(x), it's not 5 units. But yes, the amplitude is twice as much.

To get the shift, rewrite g(x) as

g(x) = 2f(x-h)

or

18 sin (7x - 5) = 2*9 sin(7(x-h))

What mus h be, to make those expressions equal?