<aside> 💡 Solve by simplify one side of the equation (only an exception with extra complicated problems)
</aside>
<aside> 💡 Arguments should be the same for factor. Think of log
</aside>
Remember the zero product property? Like in algebra, move the terms to one side first.
$AB=A$→$A(B-1)=0$ Not $B=1$
<aside> 💡 you can replace special ration like sin x to variables like u
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Why the example above, sin x = 3 is not true? Because the range of sin x is [-1,1]
| sin x | cos x | tan x | |
|---|---|---|---|
| range | [-1,1] | [-1,1] | all real number |
| domain | all real number | all real number | all real number except $\pi/2+\pi n$ |
