Mathematics · Functions

JEE Main 2025 — 3 April, Evening Shift — Question 25

If the domain of the function f(x)=log⁡7(1−log⁡4(x2−f(x)=\log _{7}\left(1-\log _{4}\left(x^{2}-\right.\right. 9x+18)9 x+18) ) is (α,β)∪(γ,δ)(\alpha, \beta) \cup(\gamma, \delta), then α+β+γ+δ\alpha+\beta+\gamma+\delta is equal to

  1. Option A:

    17

  2. Option B:

    18

    Correct
  3. Option C:

    15

  4. Option D:

    16

Answer: B

Step-by-step solution

1−log⁡4(x2−9x+18)>01-\log _{4}\left(x^{2}-9 x+18\right)>0

log⁡4(x2−9x+18)<1\log _{4}\left(x^{2}-9 x+18\right)<1

x2−9x+18<4x^{2}-9 x+18<4

x2−9x+14<0x^{2}-9 x+14<0

x∈(2,7)x \in(2,7)

x2−9x+18>0x^{2}-9 x+18>0

x∈(−∞,3)∪(6,∞)x \in(-\infty, 3) \cup(6, \infty)

figure

x∈(2,3)∪(6,7)x \in(2,3) \cup(6,7)

α+β+γ+δ=18\alpha+\beta+\gamma+\delta=18

Answer key and solution verified before publishing.

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Exam
JEE Main 2025
Subject
Mathematics
Chapter
Functions
Topic
Domain & range of functions
If the domain of the function f(x)=log 7 (1-log 4 (x 2 - . . 9 x+18)… | JEE Main 2025 PYQ with Solution · DhiX AI