CAT Algebra Practice Test 4: Cubics, Log Inequalities and Functions PYQ-Style
Built for CAT aspirants in the advanced revision stage, CAT Algebra Sectional Test 4 is a solved practice set on harder Algebra ideas. It tests cubic roots, remainder theorem, logarithmic and irrational inequalities, greatest integer function, functional equations and range of functions. Aptitude360 provides a detailed solution for every question, so each new method can be studied step by step.
What this CAT Algebra Test 4 covers
- Equations in several unknowns from word problems: prize purchases, tea stall bills and siblings' ages in AP
- Polynomials: relations between roots and coefficients of a cubic, remainder theorem and a quadratic solved with wrongly copied coefficients
- Inequalities with square roots, logarithms to a base less than one, modulus in a quadratic and the greatest integer function
- Functions: self-inverse rational functions, the functional equation for products, range over positive reals and composite quadratics with four distinct roots
- Nested surds, equal powers of different bases, AP and GP combinations and a matchstick pattern sequence
- Applied optimisation: maximising kiosk profit, area between two modulus graphs and least value of a rational expression
Key formulas and rules for this Algebra set
- Cubic \( ax^{3}+bx^{2}+cx+d=0 \): sum of roots \( =-\dfrac{b}{a} \), product \( =-\dfrac{d}{a} \)
- Remainder theorem: remainder of \( P(x)\div(x-a) \) is \( P(a) \)
- For \( 0<b<1 \): \( \log_{b}x\ge\log_{b}y \iff x\le y \), with \( x,y>0 \)
- Greatest integer: \( [x]=n \iff n\le x<n+1 \)
- AM-GM: \( \dfrac{a+b}{2}\ge\sqrt{ab} \) for \( a,b\ge 0 \)
Revision tips for advanced CAT Algebra
- Flip the inequality sign whenever the log base lies between zero and one.
- Square both sides of a root inequality only after fixing the domain and the sign of the other side.
- Treat the greatest integer as a single variable first, then convert the integer range back to real x.
- Sketch modulus graphs as V shapes to read areas and meeting points quickly.
Who this Algebra sectional test is for
It is meant for CAT and OMET aspirants who are comfortable with Algebra basics and want tougher, multi-concept practice before full-length mocks.