math problem help please?
回答 (2)
2016-07-17 4:38 pm
sin²x + cos²x = 1
sin²x + (0.3)² = 1
sin²x + 0.09 = 1
sin²x = 0.91
sinx = 0.9539 or sinx = -0.9539
cotx = 0.3/0.9539 or cotx = 0.3/(-0.9539)
cotx = 0.3145 or cotx = -0.3145
When 0° < x < 90° or 180° < x < 270° : cotx = 0.3145
When 90° < x < 180° or 270° < x < 360° : cotx = -0.3145
sin²x + (0.3)² = 1
sin²x + 0.09 = 1
sin²x = 0.91
sinx = 0.9539 or sinx = -0.9539
cotx = 0.3/0.9539 or cotx = 0.3/(-0.9539)
cotx = 0.3145 or cotx = -0.3145
When 0° < x < 90° or 180° < x < 270° : cotx = 0.3145
When 90° < x < 180° or 270° < x < 360° : cotx = -0.3145
2016-07-17 4:37 pm
cos x = 3 / 10
sin²x = 1 - 9/100 = 91/100
sin x = √91 / 10
cot x = 3 / √91
sin²x = 1 - 9/100 = 91/100
sin x = √91 / 10
cot x = 3 / √91
收錄日期: 2021-04-18 15:17:14
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