How do you find the inverse of 2x+3=y2x+3=y?
1 Answer
Jan 15, 2016
f^-1(x) = 1/2 (x - 3 )f−1(x)=12(x−3)
Explanation:
To find the inverse of this function - change the subject to x.
2x + 3 = y
rArr 2x = y - 3 rArr x = 1/2 (y - 3 ) ⇒2x=y−3⇒x=12(y−3) The inverse is usually written in terms of x.
rArr f^-1(x) = 1/2 (x - 3 ) ⇒f−1(x)=12(x−3) As a check : if x = 2 then y = 2(2) + 3 = 4 + 3 =7
now if y = 7 : then x =
1/2 (7 - 3 ) = 1/2 xx 4 = 212(7−3)=12×4=2
