Simplify the expression. (1 - cot x) / tan x - 1
substitute the value of cot x and tan x i hope u will get the ans
What?
well, keeping in mind that cot= cos/sin, and tan = sin/cos let's use that atop and below $$ \cfrac{1-cot(\theta)}{tan(\theta)-1} \implies \cfrac{ 1-\frac{cos(\theta)}{sin(\theta)} } { \frac{sin(\theta)}{cos(\theta)} } $$
hemm I missed something :/
-2
$$ \cfrac{1-cot(\theta)}{tan(\theta)-1} \implies \cfrac{ 1-\frac{cos(\theta)}{sin(\theta)} } { \frac{sin(\theta)}{cos(\theta)}-1 } $$
so, there, add both, atop and bottom, what do you get?
Add what?
the fractions :/
How?
$$ \cfrac{1-cot(\theta)}{tan(\theta)-1} \implies \cfrac{ 1-\frac{cos(\theta)}{sin(\theta)} } { \frac{sin(\theta)}{cos(\theta)}-1 } \implies \large { \color{red}{ \cfrac{ \frac{1}{1}-\frac{cos(\theta)}{sin(\theta)} } { \frac{sin(\theta)}{cos(\theta)}-\frac{1}{1} }} } $$
let's try first the numerator
(1 - cos(x))/1 - sin(X) ?
\(\frac{1}{1}-\frac{cos(\theta)}{sin(\theta)}\) what would be your LCD there?
sin (x)
right, so let's use that, to get $$ \frac{1}{1}-\frac{cos(\theta)}{sin(\theta)} \implies \frac{sin(\theta)-cos(\theta)}{sin(\theta)} $$
Ok. then the denominator would just be cos (x) - sin (x) / cos (x)
right
well, one sec
the denominator will be sin-cos/cos
right. sorry.
so sin-cos/sin / (sin-cos/cos)?
$$\large { \cfrac{ \frac{sin(\theta)-cos(\theta)}{sin(\theta)} }{ \frac{sin(\theta)-cos(\theta)}{cos(\theta)} } \implies \frac{sin(\theta)-cos(\theta)}{sin(\theta)} \times \frac{cos(\theta)}{sin(\theta)-cos(\theta)} } $$
so, there are 2 guys to cancel out, and you're left with just a function :)
cot x
Ok. Thank you!! :)
yw
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