How do you find the x intercepts for #y=-3cosx+sinx#?

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Answer 1 · 2016-08-02T00:57:47

There are infinite x intercepts; I'll find a general rule for you.

Setting the function so that #y = 0#:

#0 = -3cosx + sinx#

#0 = (-3cosx)/cosx + sinx/cosx#

#0 = -3 + sinx/cosx#

#0 = -3 + tanx#

#3 = tanx#

#x ~~ 1.25 + pin#

So, the x intercepts will occur whenever the number on the x axis equals #1.25 + pin#, n being any positive integer.

Hopefully this helps!