1. Given sinA=√2 /10 and sinB=√10 /10 where A and B are acutes angles. Find A+2B without using a calculator.
2. Given 5sin2A+3cos2A=3 where sinA=/ 0. Find the value of tan2A without using a calculator.
3. If cos2α and cos2β are the roots of the equation 9x²-8x+1=0, without solving the equation, find the value of cos(α+β)-cos(α-β) in surd form.
Trigonometric functions
2015-02-09 2:17 am
回答 (1)
2015-02-09 4:39 am
收錄日期: 2021-04-24 10:18:13
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