Math Interactive
2. Functions
2.2. Inverse functions
2.2.4. Relationship
Important
The graphs of
f
f
f
and
f
−
1
f^{-1}
f
−
1
are symmetrical about the line
y
=
x
.
y=x.
y
=
x
.
Examples
x
{x}
x
y
{y}
y
(
2
,
3
)
{\left(2 , 3 \right)}
(
2
,
3
)
(
7
,
−
7
)
{\left(7 , -7 \right)}
(
7
,
−
7
)
(
3
,
2
)
{\left(3 , 2 \right)}
(
3
,
2
)
(
−
7
,
7
)
{\left(-7 , 7 \right)}
(
−
7
,
7
)
y
=
f
(
x
)
{y=f(x)}
y
=
f
(
x
)
y
=
f
−
1
(
x
)
{y=f^{-1}(x)}
y
=
f
−
1
(
x
)
y
=
x
{y=x}
y
=
x
Get new example
f
:
x
↦
−
2
x
+
7
for
x
∈
R
,
2
<
x
<
7.
{f: x \mapsto - 2 x + 7} \allowbreak \quad \allowbreak {\textrm{for } x \in \mathbb{R}, 2 < x < 7.}
f
:
x
↦
−
2
x
+
7
for
x
∈
R
,
2
<
x
<
7.
f
−
1
:
x
↦
−
1
2
x
+
7
2
for
x
∈
R
,
−
7
<
x
<
3.
{f^{-1}: x \mapsto - \frac{1}{2} x + \frac{7}{2}} \allowbreak \quad \allowbreak {\textrm{for } x \in \mathbb{R}, -7<x<3 .}
f
−
1
:
x
↦
−
2
1
x
+
2
7
for
x
∈
R
,
−
7
<
x
<
3.
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