-->

Some Applications Of Trigonometry

Question
CBSEENMA10007732

Choose the correct option and Justify your choice.
space fraction numerator 1 plus tan squared straight A over denominator 1 plus cot squared straight A end fraction equals
(A) sec squared straight A      (B) -1     (C) cot squared straight A     (D) tan squared straight A


Solution
fraction numerator 1 plus tan squared straight A over denominator 1 plus cot squared straight A end fraction space equals space fraction numerator sec squared straight A over denominator cosec squared straight A end fraction
                    equals space fraction numerator begin display style fraction numerator 1 over denominator cos squared straight A end fraction end style over denominator begin display style fraction numerator 1 over denominator sin squared straight A end fraction end style end fraction space equals space fraction numerator 1 over denominator cos squared straight A end fraction cross times fraction numerator sin squared straight A over denominator 1 end fraction
                    equals space fraction numerator sin squared straight A over denominator cos squared straight A end fraction space equals space tan squared straight A.
Hence, correct option is (D).

Some More Questions From Some Applications of Trigonometry Chapter