Question

please solve 2 question

Answer 1

Hope this help............

Answer 2

Answer:

Step-by-step explanation:

Cos^-1 x +Cos^-1y+Cos^-1z= π+π+π

Cos^-1 x= π

Cosπ= x

-1=x

Similarly

y=-1 & z=-1

So xy= -1×-1=1

yz= -1×-1=1

zx=-1×-1=1

Sum = 1+1+1=3

Answer is. C) 3