cos(3x)=-1
1.) Using an appropriate inverse trig expression, write an equation that defines the value of 3x
2.) Solve this equation to find all possible values of the angle 3x
3.) Use algebra to find all values of x between 0 and 2pi that satisfy this equation

Question

cos(3x)=-1
1.) Using an appropriate inverse trig expression, write an equation that defines the value of 3x
2.) Solve this equation to find all possible values of the angle 3x
3.) Use algebra to find all values of x between 0 and 2pi that satisfy this equation

jdoe0001 · Answer

$\bf cos(3x)=-1\quad \textit{taking }cos^{-1}\textit{ to both sides}
\ \quad \
cos^{-1}[cos(3x)]=cos^{-1}(-1)\implies 3x=cos^{-1}(-1)$

2)   find all angles whose cosine is -1

3) solve for "x"

anonymous · Answer

Okay I think I understand but how do I solve for x? Can you help me with that please?