- #1
rohan03
- 56
- 0
Homework Statement
I need to find at least two values of x in the interval [0,∏/2]
for which f(x)= sin(x)+sin(2x)+sin(3x)=1
The Attempt at a Solution
now this is what my understanding is and this is what I have done
sin(x)+sin(2x)+sin(3x)=1
sin(x)+sin(2x)+sin(3x)-1
Now by calculation f(0) = sin(0)+sin(2x0)+sin(3x0)-1 =-1
and f(∏/2) = sin(∏/2)+sin(2x∏/2)+sin(3x∏/2)-1
that then given me = 1+0+-1 -1 =-1
but I know this is not right- as I don't get negative to positive solution to show that there is atleast two values of x for which f(x) is true!
I think I have lost the plot somewhere!
can someone look at this and tell me what's wrong and guide me to correct procedure