Signature 1 Let fx 2 Find the inverse function f1x r 2 Find
Signature: 1) Let f(x)= 2. Find the inverse function f-1(x). r- 2) Find the exact value of a) log,(16) . 100 3) Solve log, (4x-7)-2 for x
Solution
1) f(x) =1/(x-2)
f^-1(x) : plug x=y and y=x
y = 1/(x-2)
x = 1/(y-2) ---> xy -2x =1
y= (1+2x)/x
f^-1(x) = (1 +2x)/x
2) ln2(16)
now 16 = 2^4
So,log2(16) = log2(2^4) = 4*log2(2)
= 4*log2/log2 = 4
log100 = log(10^2) = 2*log10
= 2*1 =2
ln(sqrt(e) = lne^1/2 = 1/2*lne
=(1/2)lne/lne = 1/2
3) ln3(4x -7) = 2
(4x -7) = 2^3
4x -7 = 8
4x = 15
x= 15/4
