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Exponential equations and inequalities: methods

Take out a common power, substitute t = 2ˣ, read a root off a graph, and decide when an inequality keeps its sign.

📖 Start here: read the steps of the “Lesson” in order (1, 2, 3 …) and answer each question. Then continue with “Practice”.

Guide

This follows Ukrainian Grade 11 algebra §2–3: besides the same-base method, a common factor, the substitution t = 2x and the graph.

The line is the right side and the curve the left. A root is where they cross; an inequality asks where the curve is above or below the line.

Common slips: losing a term, answering t instead of x, and keeping the sign for a base between 0 and 1.