Given that sinx=261 and siny=51, and that angles x and y are both in Quadrant I, find the exact value of sin(x+y), in simplest radical form.Answer:
Q. Given that sinx=261 and siny=51, and that angles x and y are both in Quadrant I, find the exact value of sin(x+y), in simplest radical form.Answer:
Use Sine Addition Formula: To find sin(x+y), we will use the sine addition formula: sin(x+y)=sin(x)cos(y)+cos(x)sin(y).
Find cos(x) and cos(y): First, we need to find cos(x) and cos(y). Since x and y are in Quadrant I, both cos(x) and cos(y) will be positive. We can use the Pythagorean identity sin2(θ)+cos2(θ)=1 to find cos(θ) for both angles.
Calculate cos(x): For angle x, we have sin(x)=261. So, sin2(x)=(261)2=261. Using the Pythagorean identity, we get cos2(x)=1−sin2(x)=1−261=2625. Therefore, cos(x)=2625=265.
Calculate cos(y): For angle y, we have sin(y)=51. So, sin2(y)=(51)2=51. Using the Pythagorean identity, we get cos2(y)=1−sin2(y)=1−51=54. Therefore, cos(y)=54=52.
Substitute values into formula: Now we can substitute the values into the sine addition formula: sin(x+y)=sin(x)cos(y)+cos(x)sin(y)=(261)(52)+(265)(51).
Simplify expression: Simplify the expression: sin(x+y)=1302+1305=1302+5=1307.
Rationalize the denominator: To rationalize the denominator, we multiply the numerator and the denominator by 130: sin(x+y)=1307×130130=1307130.
Final simplification: Finally, we simplify the expression: sin(x+y)=1307130.
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