Question

Q.5. If f(x) =
ax+b
then f [f(x)]=....
CX-a
O 1y​

Answer 1

Answer:

d =- a

Step-by-step explanation:

f(f(x))=

cf(x)+d

af(x)+b

f(f(x))=

c

cx+d

ax+b

+d

a

cx+d

ax+b

+b

f(f(x))=

acx+bc+d

2

+dcx

a

2

x+ab+bcx+bd

=x

⇒a

2

x+ab+bcx+bd=acx

2

+bcx+d

2

x+dcx

2

Given a=−d, the above equation can also be verified

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Answer 2

Step-by-step explanation:

f(f(x))=

cf(x)+d

af(x)+b

f(f(x))=

c

cx+d

ax+b

+d

a

cx+d

ax+b

+b

f(f(x))=

acx+bc+d

2

+dcx

a

2

x+ab+bcx+bd

=x

⇒a

2

x+ab+bcx+bd=acx

2

+bcx+d

2

x+dcx

2

Given a=−d, the above equation can also be verified

mark me as brainlist