Hey can you show me how to find the x- Intercepts for cos(y+Pi) = x^2 -x - 7
I tried a bunch of different things but I can't figure it out: the answer is supposed to be 3 (I like the faces )
as always, x-intercepts occur where y = 0. so plug in y = 0, we have
$\displaystyle \cos \pi = x^2 - x - 7$
$\displaystyle \Rightarrow -1 = x^2 - x - 7$
$\displaystyle \Rightarrow x^2 - x - 6 = 0$
just solve this quadratic equation for your intercepts (there are 2 answers)