From the origin O, two displacement vectors are drawn: A has magnitude 12m and makes an angle of 135∘ with the positive x-axis; B has magnitude 15m and makes an angle of −45∘ with the positive x-axis (i.e., 45∘ below it).
a. (i) Express A and B individually in unit-vector notation.
b. (ii) Obtain the resultant displacement R=A+B in unit-vector form.
c. (iii) Calculate the magnitude of R and the angle it makes with the positive x-axis, quoting the angle to the nearest degree.