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A. Domain: all real numbers; Range: all real numbers

B. Domain: all real numbers; Range: y>2

C. Domain: all real numbers; Range: y>0

D. Domain:x<1; Range: y>2

E. Domain: x<1; Range: all real numbers

1 Answer
May 4, 2018

Answer is option B i.e. Domain: all real numbers; Range: y>2

Explanation:

As f(x)=5(4)^x+2

x can take any value from -oo and oo and hence domain is all real numbers.

As x->-oo, f(x)=5(4)^(-oo)+2=5/4^oo+2=0+2, hence f(x)->2 and hence minimum value of f(x) is 2

and when x->oo f(x)->oo

Hence range is y>2

and answer is option B i.e. Domain: all real numbers; Range: y>2