Curriculum
Pure Mathematics — Second Secondary
Unit 1: Real Functions and Curve Sketching
0/8
Unit 2: Exponents and Logarithms
0/12
Unit 3: Limits
0/6
Unit 4: Trigonometry
0/4
Text lesson
Finding Limits Algebraically
Finding Limits Algebraically
Common mistakes
Common mistakes
Key points
Cancelling added terms(x2 + 9) / (x + 3) is not equal to x2 / x. Cancelling applies only to factors.
Treating 0/0 as 0 or as 1this is an indeterminate form, so it needs simplification rather than a direct conclusion.
Wrong conjugatemultiplying (√ − 2) by (√ + 2) gives a difference of squares, and the numerator and the denominator must both be multiplied.
Forgetting to substitute after simplifyingonce the expression is simplified, substitute the point into the simpler form.
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