Question

f(x)=square root(x+4)-2

Answer 1

@ellensmith Hi,

\(\huge \color{red}{\text{Welcome to Open Study}}\ddot\smile\)

so ,\(f(x)=\sqrt{x+4}-2\)
what needs to be done ?? can you please post the entire question.

Answer 2

find the inverse

Answer 3

right, so let \(y=\sqrt{x+4}-2\)
interchange 'x' and 'y'
\(x=\sqrt{y+4}-2\)
now can you isolate 'y' from this equation ?? y=....
that will be your inverse function.

Answer 4

not sure

Answer 5

\(x=\sqrt{y+4}-2\)
add 2 on both sides, what you get ?

Answer 6

x+2+square root y+4

Answer 7

you meant, \(x+2=\sqrt{y+4}\), right ?
now square both sides, what you get ?

Answer 8

x^2+4x+4=y+4

Answer 9

correct! good,
now subtract 4 from both sides, what you get ?

Answer 10

y=x^2+4x

Answer 11

see, how easily 'y' was isolated ...
so, your inverse function is \(f^{-1}(x)=x^2+4x\)
any doubts ?

Answer 12

Thanks...now one more ,please solve for x 4^x=80 or 4 to the x power _80

Answer 13

do you know logarithms ?
and next time, please make a separate post for new question....

Answer 14

sort a

Answer 15

do you have options/choices for 4^x=80 in which there are log terms ??

Answer 16

just have to solve for x

Answer 17

ok, then take log on both sides.
use \(\log x^n=n\log x\)
so, what you get for \(\log 4^x=.... ??\)

Answer 18

not sure

Answer 19

try again.....if you notice, the exponent (n) becomes the co-efficient of log term (log x)
so, what about 4^x ?

Answer 20

lost