Pathshala
JEE Advanced maths, worked one sign at a time.
Short video solutions to previous-year JEE Advanced questions, in Hindi, English and Bengali. Every step is said out loud and shown on screen, including each double negative.
Step through it: JEE Advanced 2017, Paper 2, Q37
Find the plane through (1, 1, 1) perpendicular to the planes 2x + y − 2z = 5 and 3x − 6y − 2z = 7.
n
n₁ = (2, 1, −2), n₂ = (3, −6, −2)
x
1(−2) − (−2)(−6) = −2 − 12 = −14
y
(−2)(3) − 2(−2) = −6 + 4 = −2
z
2(−6) − 1(3) = −12 − 3 = −15
×
n₁ × n₂ = (−14, −2, −15) → n = (14, 2, 15)
P
14(x − 1) + 2(y − 1) + 15(z − 1) = 0
=
14x + 2y + 15z − 31 = 0
✓
14x + 2y + 15z = 31
Minus times minus is plus, so (−2)(−6) = +12. Subtracting it gives −12.
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The first solution, in three languages
How each solution is made
From the official paper
Questions come from the official JEE Advanced papers, and answers are compared with the official key.
Every number computed twice
A program computes each value on screen. A second, independent script must get the same value.
Spoken as it appears
Each sign change is said at the moment it appears on screen, with captions in the same language.
Ten years of papers, one question at a time
Our question bank lists 352 mathematics questions from 20 official papers. This is what is published so far.
20171 / 36
20180 / 36
20190 / 36
20200 / 36
20210 / 38
20220 / 36
20230 / 34
20240 / 34
20250 / 32
20260 / 34
Common questions
- Is Pathshala free?
- Yes. Every solution is free to watch on YouTube.
- Which languages do you teach in?
- Each solution is published in Hindi, English and Bengali, as a separate video with captions in that language.
- Is this connected with the IITs or NTA?
- No. Pathshala is independent. Official papers and notices remain the final authority.