Q. u=(−5,−8)Find the direction angle of u. Enter your answer as an angle in degrees between 0∘ and 360∘ rounded to the nearest hundredth.θ=□∘
Calculate Tangent Ratio: To find the direction angle of the vectoru=(−5,−8), we need to calculate the angle that this vector makes with the positive x-axis. The direction angle, often denoted as θ, can be found using the arctangent function (tan−1 or atan), which gives us the angle whose tangent is the ratio of the y-coordinate to the x-coordinate of the vector.
Use Arctangent Function: First, we calculate the tangent of the angle θ using the coordinates of u. The tangent of θ is the ratio of the y-coordinate to the x-coordinate.tan(θ)=xy=−5−8=58
Add 180 Degrees: Next, we use the arctangent function to find the angle θ whose tangent is 58. However, since the vector is in the third quadrant (both x and y are negative), we need to add 180∘ to the angle we get from the arctangent function to find the correct direction angle that is between 0∘ and 360∘.θ=atan(58)+180∘
Calculate Arctangent: We calculate the arctangent of 58 using a calculator and then add 180° to find the direction angle.θ≈atan(58)+180°≈58.00°+180°≈238.00°
Round to Nearest Hundredth: Finally, we round the direction angle to the nearest hundredth as requested. θ≈238.00∘
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