Formula to get the resolved part of a vector vecV→V along the direction making an angle thetaθ with it is given by
vecV_"resolved part"=vecVcostheta→Vresolved part=→Vcosθ
vecA→A makes an angle theta=0^@θ=0∘ with the X-axis and it makes an angle theta=90^@θ=90∘ with the Y-axis.
So its resolved part along X-axis
vecA_x=vecAcos0^@→Ax=→Acos0∘
And its resolved part along Y-axis
vecA_y=vecAcos90^@→Ay=→Acos90∘
Again vecB→B makes an angle theta=(180^@-60^@)θ=(180∘−60∘) with the X-axis and it makes an angle theta=30^@θ=30∘ with the Y-axis.
So its resolved part along X-axis
vecB_x=vecBcos(180^@-60^@)=-Bcos60^@→Bx=→Bcos(180∘−60∘)=−Bcos60∘
And its resolved part along Y-axis
vecB_y=vecBcos30^@→By=→Bcos30∘