Page 111 - E-Book SBMPTN Saintek

2.­ Jika­f(x)­=­y­maka­f­ ­(y)­=­x
–1
3.­ Fungsi­ f­ mempunyai­ fungsi­ invers­ jika­ f­
korespon densi (berpasangan) satu-satu.
4.­ Sifat­­fungsi­invers:
I
•­ f f − 1 = f  − 1 f == x

•­ (g f) = − 1 f  − 1 g − 1

Rumus­Ringkas­Beberapa­Fungsi­Invers:

x b
−
1.­ f(x)­=­ ax b →­ f (x)­=
-1
+
a
1
)
2.­ f(x)­=­ x b →­ f (x)­=(x ba
−
+
-1
a
2
3.­ f(x)­= ax b →­ f (x)­= x − b
-1
+
a
ax b − dx b
+
+
4.­ f(x)­= →­ f (x)­=
–1
+
−
cx d cx a
xb
+
-1
2
b
5.­ f(x)­= ax − →­ f (x)­=­ ±
a
2
6.­ f(x)­=­ax ­+­bx­+­c­
+
−± 4ax D
b
-1
f (x)­=­
2a
1
–1
a
7.­­ f(x)­=­ log nx → f (x)­=­ .a x
n
1
8.­­ f(x)­=­a nx­­­­­ → f (x)­=­ . logx
–1
a
n

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