Question

If cos A = sin/2sinC, then ΔABC is

(a) Equilateral

(b) Isosceles

(c) Right angled

(d) None of these

Answer 1

Answer:

❀ʀᴇǫᴜɪʀᴇᴅ ᴀɴsᴡᴇʀ:

Because of the lack of grouping symbols, there are three questions here, all starting “What s the triangle ABC is”

cosB=sinA2sinC or cosB=sinA2sinC or cosB=sinA2sinC

The first two are unlikely to be finished since they depend on R. So we consider the last which becomes

2cosB=ac⇒a2+c2−b2ac=ac⇒b=c.

So the triangle is isosceles.

so,the answer is (b) Isosceles

$\sf\blue{hope \: this \: helps \: you!! \: }$

Answer 2

Answer:

Hope this will help you mate