Question #8471c

1 Answer
Dec 31, 2014

Answer:

The original powers of the 2 brackets are #1/2# i.e. square roots. You can still see them when you open the question. For some reason they appear as ones!

Explanation:

#2<=x<=4#

Your function is the sum of two square roots. Your square roots cannot have negative argument (you cannot find a real number which is solution of a negative square root).
So you must avoid negative arguments; so it must be:
#2x-4>=0# and (at the same time) #-5x+20>=0#

The first gives you: #x>=2#
The second gives you: #x<=4#
BUT, they have to work together in your function!
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The shaded region (#2<=x<=4#) is where your function can accept values of #x#.