Determine the domain
\[(h o g)(x)\] \[h(x)=\frac{ 1+2x }{ 1-2x }\] \[g(x)=\sqrt{1-2x}\]
first frite the expretion for hog(x)
\[hog(x)=\frac{1+2\sqrt{1-2x}}{1-2\sqrt{1-2x}}\]
then
now, there will be to evident conditions for this expretion to have any meaning: 1-2x>0 and 1-2sqrt(1-2x) not equal to 0
and
for the first one: 1>2x it means x<1/2 for the 2ยบ one: 1-2sqrt(1-2x)=0 1=2sqrt(1-2x) 1/2=sqrt(1-2x) 1/4=1-2x 2x=1-1/4=3/4 x=3/8 this value of x will make it 0, so need to be excluded from domain. Now just combine bouth conditions: x<1/2 and x not equal to 3/8
|dw:1348395962436:dw|
@AravindG please help me with this
it gives me the domain (-inf, 1/2) but i don't know how he come up with that
in first equation for h(x) to be defined 1-2x should not be equal to 0
find the value of x for which this happens and remove it from the domain
why?
because a fraction is not defined with denominator=0
oh that's how he got the 1/2
and then
Join our real-time social learning platform and learn together with your friends!