Please see another question below- helpful feedback is appreciated- thanks.
1. For which of the following functions is f(a+b)= f(a)+f(b) for all positive numbers a and b?
- f(x)=x2
- f(x)= x+1
- f(x)= rootX
- f(x)= 2/x
- f(x)= -3x
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sujaysolanki
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hemanth28
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pretty simple...
f(a)+f(b)=f(a+b)
check with each options if this is satisfied.
if f(x)=x^2.
than f(a)+f(b) =a^2+b^2 which is not equal to (a+b)^2.
similarly for others too it doesnt go...except if f(x)=-3x
f(a)+f(b) = -3a-3b=-3(a+b) =f(a+b).
f(a)+f(b)=f(a+b)
check with each options if this is satisfied.
if f(x)=x^2.
than f(a)+f(b) =a^2+b^2 which is not equal to (a+b)^2.
similarly for others too it doesnt go...except if f(x)=-3x
f(a)+f(b) = -3a-3b=-3(a+b) =f(a+b).
