What is sin and cos if tan = 1/2 and sin>0?

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What is sin and cos if tan = 1/2 and sin&gt;0?

Juliette Mahoney · Accepted Answer

If the sine and tangent of an angle           &amp;#x3B1;       are positive, the angle lies in the first quadrant, meaning both the sine and cosine are positive. Since                tan       &amp;#x3B1;          =                     sin         &amp;#x3B1;                       cos         &amp;#x3B1;                 So                         sin         &amp;#x3B1;                       cos         &amp;#x3B1;                 =            1       2          Trigonometry is based on                          sin         2              &amp;#x3B1;          +                     cos         2              &amp;#x3B1;          =     1     So, let&#039;s use it for is                cos       &amp;#x3B1;          =     2            sin       &amp;#x3B1;                                  sin         2              &amp;#x3B1;          +                     cos         2              &amp;#x3B1;          =     1                             sin         2              &amp;#x3B1;          +     4                     sin         2              &amp;#x3B1;          =     1     &amp;#x21D2;                     sin         2              &amp;#x3B1;          =            1       5          &amp;#x21D2;            sin       &amp;#x3B1;          =                     5              5                         cos       &amp;#x3B1;          =     2            sin       &amp;#x3B1;          =     2                     5              5

What is sin and cos if tan = 1/2 and sin>0?

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