question

Asked by arindeep.singh | 20th Aug, 2020, 06:58: PM

Expert Answer:

Q: To express cos A, tan A and sec A in terms of sinA.
Answer: 
As we know that sin2A+cos2A=1
rightwards double arrow cos squared straight A equals 1 minus sin squared straight A space
rightwards double arrow cosA equals square root of 1 minus sin squared straight A end root space... space left parenthesis straight i right parenthesis
tanA equals sinA over cosA equals fraction numerator sinA over denominator square root of 1 minus sin squared straight A end root end fraction space... space From space left parenthesis straight i right parenthesis
rightwards double arrow tanA equals fraction numerator sinA over denominator square root of 1 minus sin squared straight A end root end fraction space... space left parenthesis ii right parenthesis
secA equals 1 over cosA equals fraction numerator 1 over denominator square root of 1 minus sin squared straight A end root end fraction space... space From space left parenthesis straight i right parenthesis
rightwards double arrow secA equals fraction numerator 1 over denominator square root of 1 minus sin squared straight A end root end fraction

Answered by Renu Varma | 21st Aug, 2020, 12:31: PM