Question #8bcb5

1 Answer
Jan 12, 2015

Well, I think you are right; if you have #sqrt(225-x^2)# the allowed values for #x# are those for which the argument of the square root is #>=0#, i.e.:
#225-x^2>=0# so that:
#x<=+-15#
This represents the interval in between the values of #-15# and #+15#:
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You can check using a value in the middle of the interval such as #x=0# which gives you:
#sqrt(225)=15# that is ok.