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| Natural Cosine Tables |
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| A part of the natural cosine tables is given below: |
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| Find from the tables the value of |
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| (i) cos 37o (ii) cos 37o 42' (iii) cos 37o 45' |
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| (i) cos 37o Find 37o on the 'Natural Cosines' table in 'A' group. As there are no minutes, the value is read horizontally under the 0' column. |
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 cos 37o = 0.7896 |
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| (ii) cos 37o 42' |
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| Look horizontally along 37o column and vertically under 42o in 'B' group. |
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 cos 37o 42' = 0.7912 |
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| (iii) cos 37o 45' As in (ii) read for cos 37o 42' |
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| and for 3' read from 'C' group. |
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| cos 37o 45' = 0.7907 |
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| To find q when cosine ratio is known |
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If  , find q |
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| The reading can be obtained from t-tables. |
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