You are here
Question 4 (i) - Proving not true/false (by giving counter examples) - Mathematical Reasoning
Last updated at August 14, 2026 by Teachoo
Proving not true/false (by giving counter examples)
Mathematical Reasoning
Concept wise
- Statements
- Writing negation of statements
- Negation - Checking if true or not
- Finding Compound Statement
- Words 'And' & 'Or'
- Inclusive and exclusive or
- Quantifiers
- Contrapositive and converse
- If then
- If and only if
-
Proving not true/false (by giving counter examples)
- Proving True - If and only if
- Proving True - By Contrapositive
- Proving True - By Contradiction
- Necessary and sufficient condition
Transcript
Question 4 By giving a counter example, show that the following statements are not true. p: If all the angles of a triangle are equal, then the triangle is an obtuse angled triangle. Since all angles of triangle are equal, each angle is 60° But no angle greater than 90° So this triangle is not obtuse angled triangle Hence the given statement is false
