Mathematics · Logrithms

JEE Main 2026 — 23 January, Evening Shift — Question 7

The sum of all the real solutions of the equation log⁡(x+3)(6x2+28x+30)=5−2log⁡(6x+10)(x2+6x+9)\log _{(x+3)}\left(6 x^{2}+28 x+30\right)=5-2 \log _{(6 x+10)}\left(x^{2}+6 x+9\right) is equal to :

  1. Option A:

    22

  2. Option B:

    11

  3. Option C:

    00

    Correct
  4. Option D:

    44

Answer: C

Step-by-step solution

log⁡x+3[(x+3)(6x+10)]=5−2log⁡6x+10(x+3)2\log _{x+3}[(x+3)(6 x+10)]=5-2 \log _{6 x+10}(x+3)^{2}

1+log⁡x+3(6x+10)=5−4log⁡6x+10(x+3)1+\log _{\mathrm{x}+3}(6 \mathrm{x}+10)=5-4 \log _{6 \mathrm{x}+10}(\mathrm{x}+3)

Let log⁡(x+3)(6x+10)=A\log _{(x+3)}(6 \mathrm{x}+10)=\mathrm{A}

⇒A+4 A=4\Rightarrow \mathrm{A}+\frac{4}{\mathrm{~A}}=4 or A=2\mathrm{A}=2

⇒log⁡(x+3)(6x+10)=2\Rightarrow \log _{(\mathrm{x}+3)}(6 \mathrm{x}+10)=2

⇒6x+10=(x+3)2\Rightarrow 6 \mathrm{x}+10=(\mathrm{x}+3)^{2}

⇒6x+10=x2+9+6x\Rightarrow 6 \mathrm{x}+10=\mathrm{x}^{2}+9+6 \mathrm{x}

⇒x2=1,x=±1\Rightarrow \mathrm{x}^{2}=1, \mathrm{x}= \pm 1

So sum of roots =0=0

Answer key and solution verified before publishing.

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Exam
JEE Main 2026
Subject
Mathematics
Chapter
Logrithms
Topic
Logarithmic Equations
The sum of all the real solutions of the equation log (x+3) (6 x 2… | JEE Main 2026 PYQ with Solution · DhiX AI