f(x)=y=x−3x−2
∴x=y−13y−2
∴f−1(x)=x−13x−2
&g(x)=y=2x-3
∴x=2y+3
∴g−1(x)=2x+3
∵f−1(x)+g−1(x)=213
x−13x−2+2x+3=213
∴x2−5x+6=0 has roots x1,x2
∴ sum of roots x1+x2=5
JEE Main 2021 — Mathematics Algebra
Let f:R−3→R−1 be defined by f(x)=x−3x−2. Let g:R→R be given as g(x)=2x−3. Then, the sum of all the values of x for which f−1(x)+g−1(x)=213 is equal to
Held on 18 Mar 2021 · Verified 6 Jul 2026.
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