#need help with queston d (ii)

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steep gale
ancient forumBOT
steep gale
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what i got so far^

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first img is the solution and the second img is the one i need help with

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this is question ii of d

jaunty bloom
# steep gale

Division by sin(x) causes you to lose a solution or solutions

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Instead multiply by cos(x) as we exclude the case cos(x) = 0

Then bring both terms on one side and factor sine and use zero product theorem.

steep gale
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sorry im still a bit confused

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so we dont divide sin(x)/tan(x)?

jaunty bloom
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You lose sine

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By that

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Now if you bring sine to the other side you can factor sine and use zero product theorem

steep gale
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wait what happened with tan(x), why is it cos(x)?

leaden fieldBOT
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adonhs

587715738484211754.png
jaunty bloom
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Now it's correct, thanks

steep gale
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ohh ok

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i understand now

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and then we subtract sin from both sides and apply zero product thorem im assuming

jaunty bloom
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yes

steep gale
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u know for the solution right

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do you know why its

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positive and negative

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and not just positive

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the plus-minus sign

jaunty bloom
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Because of cosine's symmetry

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For example

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,w plot y = cosx and y = 1/2

leaden fieldBOT
jaunty bloom
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Due to its symmetry property it has the +- sol.

steep gale
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ohh i see

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alr thanks man

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appreciate it

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.close