Please help in solving... (1 Viewer)

[Drewk]

Find all real numbers, y,which satisfy the equation
4^y -9(2)^y + 8=0
Please show all relevant working

 

[Fus Ro Dah]

 

[twinklegal19]

 

[Drewk]

Could you also help me with this one...
determine the greatest value of the function f(y) = 17 + 4y -x^2

 

[Fus Ro Dah]

Umm... are you sure you typed it out correctly? If the following is a function of y, then I presume -x^2 is constant. If so, then the greatest value of the function f(y) is infinity because we have a linear function, which is unbounded from above and below.

 

[Drewk]

Umm... are you sure you typed it out correctly? If the following is a function of y, then I presume -x^2 is constant. If so, then the greatest value of the function f(y) is infinity because we have a linear function, which is unbounded from above and below.

Sorry i did make a mistake it should be y^2
thx

 

[Fus Ro Dah]

1. We can use basic Calculus.



2. We can find the vertex using the formula y = -b/2a = 2. Subbing it back into the function f gives us the same as above.