no it isn't. 2cos(x) is 2 multiplied by cos(x), cos (2x) is cos(2 multiplied by x) meaning 2x is the angle you're taking the cosine of. if you want to know what cos(2x) look up the double angle rule.
Answer:
1260 is cost price and 140 is profit.
Step-by-step explanation:
The extraneous root is
x = 2
F(2) means that you are plugging in 2 for x, while f(x)=2 means that the equation equals 2 (y=2) at a certain x value.
