Suppose ABC is a triangle with 3 acute angles A, B and C The points whose co ordinates are - Maths - Coordinate Geometry

Question

Suppose ABC is a triangle with 3 acute angles A, B and C The points
whose co ordinates are (cos B - sinA, sin B- cos A) can be in the
:-
1) 1st and 2nd quadrant
2) 2nd and 3rd quadrant
3) 3rd and 4th quadrant
4) 2nd qudrant only
Please answer with proper explanation

Lovina Kansal · Accepted Answer

Dear student
Since ABC is a acute angle Therefore,A+B>π2⇒A>π2-B⇒sinA-cosB>0⇒cosB-sinA<0    
(1)Again,B>π2-A⇒sinB>cosA⇒sinB-cosA>0     
(2)From (1) and (2) x-coordinate is -ve and y-coordinate is +ve⇒lie in 2nd quadrant only
Regards

Suppose ABC is a triangle with 3 acute angles A, B and C. The points whose co ordinates are (cos B - sinA, sin B- cos A) can be in the :- 1) 1st and 2nd quadrant 2) 2nd and 3rd quadrant 3) 3rd and 4th quadrant 4) 2nd qudrant only Please answer with proper explanation

Suppose ABC is a triangle with 3 acute angles A, B and C. The points whose co ordinates are (cos B - sinA, sin B- cos A) can be in the :-
1) 1st and 2nd quadrant
2) 2nd and 3rd quadrant
3) 3rd and 4th quadrant
4) 2nd qudrant only
Please answer with proper explanation