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Pre-Cal Help Please!!! (See Attachment)

Pre-Cal Help Please!!! (See Attachment)-example-1
User Leogout
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1 Answer

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sin(x) = 1/2 in the first quadrant => x = 30°

cos(y) = (√2) / 2 in the first quadrant => y = 45°

=> x + y = 75°

=> tan (x + y) = tan (75°) = 3.73

Also you can use:

tan (x +y) = sin(x + y) / cos(x + y)

sin (x + y) = sin(x)cos(y) + cos(x)sin(y)

sin(x) = 1/2 in the first quadrant => cos(x) = (√3) / 2
cos(y) = √2 / 2 in the first quadrant => sin(xy = √2 / 2

=> sin(x+y) = (1/2)(√2/2) + (√3)/2 (√2)/2 = √2 / 4 + √6 / 4

cos(x + y) = cos(x) cos(y) - sin(x)(sin(y) = (√3)/2 (√2)/2 - (1/2)(√2)/ 2 = √6 /4 - √2 / 4

=> tan(x +y) = [√2 / 4 + √6 /4] / [√6 / 4 - √2 / 4] = [√2 + √6] / [√6 - √2] = 3.73
User Gaurav Ingalkar
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