and what is the domain of y=ln(3-x)
please show your work
thanksss
please show your work
thanksss
-
Well, the domain of (x + 3) / (x^2 + 9) would be all the values for which the expression is defined. The way I wrote it, the domain would be R (all real numbers). The way you wrote it, it would be:
x + (3 / x^2) + 9, which would leave 3 / x^2 undefined for x = 0, so it would be R \ { 0 }
ln ( 3 - x ) is only defined for values where you try to take the natural logarithm of a nonzero, positive number. So the domain would thus be (<-, 3)
x + (3 / x^2) + 9, which would leave 3 / x^2 undefined for x = 0, so it would be R \ { 0 }
ln ( 3 - x ) is only defined for values where you try to take the natural logarithm of a nonzero, positive number. So the domain would thus be (<-, 3)
-
Domain of the first is all real numbers since the only possible stipulation might be that you can't divide by zero but since there is no number that will give zero in the denominator then it is all real numbers.
ln has a domain of all positive real numbers. so 3-x must be greater than zero. i.e. 3-x > 0 or 3 > x. So the domain is all real numbers such that x is less than 3.
ln has a domain of all positive real numbers. so 3-x must be greater than zero. i.e. 3-x > 0 or 3 > x. So the domain is all real numbers such that x is less than 3.
-
for fraction to be defined, the denominator (here, x² + 9) must NOT be equal to zero
because if u try on ur calculator to divide
1000 / 0 = MATH ERROR !!!
so
x² + 9 ≠ 0
x² ≠ - 9
that true
now find the sqrt root of x² and -9
sqrt(x²) = x
sqrt(-9) = UNDEFINED !
so
x² ≠ - 9 ALWAYS
so the domain is infinity
x ϵ ]-∞, +∞[
because if u try on ur calculator to divide
1000 / 0 = MATH ERROR !!!
so
x² + 9 ≠ 0
x² ≠ - 9
that true
now find the sqrt root of x² and -9
sqrt(x²) = x
sqrt(-9) = UNDEFINED !
so
x² ≠ - 9 ALWAYS
so the domain is infinity
x ϵ ]-∞, +∞[
-
Amazing! Is this what you are looking for? http://milanstreet.info/426334/domains
-
the domain is all real numbers is expect for zero, because it cause the division by zero, which is illegal.
(-infinity,0),(0,infinity)
(-infinity,0),(0,infinity)
-
(x+3) / x^(2)+9:
[-3, -->)
http://i53.tinypic.com/2cgc51y.png
[-3, -->)
http://i53.tinypic.com/2cgc51y.png