if-f-2x-1-x-2-3x-2-find-f-2-

Question Number 169319 by otchereabdullai@gmail.com last updated on 28/Apr/22

if f (2 x - 1) = x^{2} - 3 x + 2, find f (2)

Commented by infinityaction last updated on 28/Apr/22

x \to \frac{x + 1}{2}

f (x) = {(\frac{x + 1}{2})}^{2} - 3 (\frac{x + 1}{2}) + 2

f (2) = \frac{9}{4} - \frac{9}{2} + 2

f (2) = - \frac{1}{4}

Commented by otchereabdullai@gmail.com last updated on 28/Apr/22

Thank you

Answered by alephzero last updated on 28/Apr/22

f (2 x - 1) = x^{2} - 3 x + 2

2 = 2 x - 1

\Rightarrow x = 1.5

\Rightarrow f (2 (1.5) - 1) = 1 . 5^{2} - 3 (1.5) + 2

= 2.25 - 4.5 + 2 = - 0.25

Commented by otchereabdullai@gmail.com last updated on 28/Apr/22

thank you