How do you find the amplitude and period of #f(x) = 3 cos (2/3)x#?
1 Answer
Sep 16, 2017
Explanation:
#"the standard form of the cosine function is"#
#color(red)(bar(ul(|color(white)(2/2)color(black)(y=acos(bx+c)+d)color(white)(2/2)|)))#
#"where amplitude "=|a|," period "=(2pi)/b#
#"phase shift "=-c/b," vertical shift "=d#
#"here "a=3,b=2/3,c=d=0#
#rArr" amplitude "=|3|=3," period "=(2pi)/(2/3)=3pi#
