Limits of trigonometric functions and its Gemotrical Proof

During the study of limits of function in calculus what I observed that we can't know the behavior of any function until we know about the limit of functions .
Most of the proof of limits we can proved by algebraically but limits of trigonometrical function usually proved by Geometrical way .
For most of beginner  student of calculus has some difficulty of  understanding  the following limit

Priyanka and Mithi

Difference between axioms,postulates, theorems, problem, Proposition ,corollaries,hypothesis etc…

AXIOMS :  A  general statement admitted without proof to be called an axioms .
POSTULATES: In geometry a geometric statement admitted without proof to be true is called postulates.
THEOREMS: A statement to be proved is called a theorem.
PROBLEM: A construction to be made so that it satisfy certain given condition is called problem.
PROPOSITION : A statement of a theorem to be proved or a problem to be solved is called a proposition.
COROLLARIES: A truth that follows from another with little or no proof  is called a corollaries.
HYPOTHESIS: A supposition made in an argument is called an hypothesis.
DISCUSSION : The examination of a problem with reference to all possible conditions , particularly with respect to the number of the number of solutions, is called the discussion of the problem.
DETERMINATE:A problem that has a definite number of solution is said to be determinate.
INDETERMINATE:A problem that has an indefinite number of solution is said to be indeterminate.
IMPOSSIBLE : A problem that has no solution is said to be impossible.

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