Eric Nicholas K's answer to Shalyn's Secondary 3 A Maths Singapore question.
done
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A rough idea, but beware of the addition angle formula.
Date Posted:
3 years ago
We can cancel the tan for the numerator and denominator?
In this case, I actually “multiplied” the entire of the LHS and the RHS by the denominator (Tan theta + 1) to eliminate the denominator.
Since the RHS is 0, it remains 0 after the multiplication.
As far as possible, we try to not cancel tan theta as cancellations can cause the loss of some solutions.
For example,
Tan x sin x = tan x
If we cancel the tan x on both sides, we will lose out the solutions arising from tan x = 0, since this is a possible scenario which gets eliminated by cancelling out the tan x.
Since the RHS is 0, it remains 0 after the multiplication.
As far as possible, we try to not cancel tan theta as cancellations can cause the loss of some solutions.
For example,
Tan x sin x = tan x
If we cancel the tan x on both sides, we will lose out the solutions arising from tan x = 0, since this is a possible scenario which gets eliminated by cancelling out the tan x.
Oh ok got it thanks
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