Answer: see proof below
<u>Step-by-step explanation:</u>
Given: A + B + C = π → A = π - (B + C)
→ B = π - (A + C)
→ C = π - (A + B)
Use Sum to Product Identity: sin A - sin B = 2 cos [(A + B)/2] · sin [(A - B)/2]
Use the following Cofunction Identity: cos (π/2 - A) = sin A
<u>Proof LHS → RHS:</u>
LHS: sin A - sin B + sin C
= (sin A - sin B) + sin C
Answer:
The required point is, (7, -2)
Step-by-step explanation:
The straight line passing through (0,0) and (2,7) is,
y =
⇒ y = 3.5x --------------(1)
Now, the straight line perpendicular to this line and passing through (0, 0) is
y =
⇒ 7y + 2x = 0 -------------(2)
Let, (h,k) be the required point.
then, it is on the line 7y + 2x = 0
⇒7k + 2h = 0
⇒k = ------------(3)
Again, distance from (0,0) of (h, k) is same as that of (2,7)
⇒
⇒ = 53 [putting the value of k from (3)]
⇒ = 49
⇒h = 7 [since, (h,k) is in 4th quadrant, so,h >0]
So, k = -2 [putting the value of h in (3)]
So, the required point is, (7, -2)
