PREPWISER.

Quadratic Equations & Polynomial Inequalities formula sheet

Every formula in the Quadratic Equations & Polynomial Inequalities chapter for JEE Main, with one line on when it applies. Topic 1 is open to everyone; sign in free to read all 24 and download the PDF.

Read the first part free. Sign in free with Google to read the rest and download the PDF: 2 A4 pages.2 A4 pages, ready to print.

How we count: 7× asked means 7 past JEE Main questions in the PrepWiser bank needed that formula, and "last" is the latest year one appeared. ★ marks formulas asked 8 or more times.

Roots and their nature

Quadratic formula
8× asked, last 2026
x=−b±D2a,D=b2−4acx=\frac{-b\pm\sqrt D}{2a},\qquad D=b^2-4ac
Real a,b,ca,b,c: D>0D>0 two real, D=0D=0 equal (−b/2a-b/2a), D<0D<0 conjugate pair. a+b+c=0a+b+c=0: roots 1 and c/ac/a.
Rational and integer roots
3× asked, last 2025
a,b,c∈Q: roots rational  ⟺  D is a perfect squarea,b,c\in\mathbb Q:\ \text{roots rational}\iff D\text{ is a perfect square}
x2+bx+cx^2+bx+c (integers): integer roots iff DD is a perfect square.
Conjugate roots
4× asked, last 2025
p+iq root⇒p−iq rootp+q root⇒p−q root\begin{aligned}&p+iq\text{ root}\Rightarrow p-iq\text{ root}\\&p+\sqrt q\text{ root}\Rightarrow p-\sqrt q\text{ root}\end{aligned}
First needs real, second rational coefficients. x2+kx+k2=0x^2+kx+k^2=0: roots kωk\omega, kω2k\omega^2.
Sum of squares = 0
4× asked, last 2024
(px−q)2+(qx−r)2=0 ⇒ x=qp=rq(px-q)^2+(qx-r)^2=0\ \Rightarrow\ x=\frac qp=\frac rq
Real terms: each square is 0, so p,q,rp,q,r in G.P. with ratio xx.

Practise Quadratic Equations & Polynomial Inequalities questions as you read. Free, and you can start without signing up.

Practise Quadratic Equations & Polynomial Inequalities

20 more formulas in 5 topics

Sum, product and symmetric functions; Forming equations and common roots; Sign, range and location of roots; Equations reducible to quadratics; and Modulus, logarithms and inequalities. Read the first part free. Sign in free with Google to read the rest and download the PDF.

Sign in to read the restYou come straight back to this spot.Download the PDF

Sum, product and symmetric functions

  • Sum and product14×
  • Symmetric functions13×
  • Power sums9×
  • Cubic: Vieta5×

Forming equations and common roots

  • Equation with given roots5×
  • Transformed roots3×
  • One common root8×
  • Both roots common1×

Sign, range and location of roots

  • Sign of a quadratic3×
  • Maximum and minimum7×
  • Range of a quadratic ratio2×
  • Signs of the roots5×
  • Roots relative to k4×

Equations reducible to quadratics

  • Substitution ranges13×
  • Reciprocal equations8×
  • Higher degree8×
  • Square-root equations3×

Modulus, logarithms and inequalities

  • Modulus14×
  • Wavy curve4×
  • Logarithms4×

Practise Quadratic Equations & Polynomial Inequalities next

About 125 past JEE Main questions from this chapter, with instant answer checking and step-by-step solutions where available. Free, and you can start without signing up.

Practise Quadratic Equations & Polynomial Inequalities

Also free on PrepWiser

Spotted a mistake? Write to support@prepwiser.in and we will fix it in the next version.

Version 1, October 2026. Free to share for study, as it is. Please don't sell it or remove the PrepWiser name.

PractiseSign in to read all 24Download PDF
Free with Google, takes a few seconds2 pages, free