Answer:
Step-by-step explanation:
C.
Answer:
Step-by-step explanation:
a + 143 = 180 {Linear pair}
a = 180 - 143
a = 37
37 + 93 + b = 180 {Angle sum property of triangle}
130 + b = 180
b = 180 - 130
b = 40
c + b = 90
c + 40 = 90
c = 90 - 40
c = 50
d + 120 = 180 {Linear pair}
d = 180 - 120
d = 60
? = 60 + 40 {Exterior angle property of triangle}
? = 100
Step-by-step explanation:

We start with Left hand side
We know that csc(x) = 1/ sin(x)
So csc(2x) is replaced by 1/sin(2x)

Also we use identity
sin(2x) = 2 sin(x) cos(x)

4 divide by 2 is 2
Now we multiply top and bottom by sin(x) because we need tan(x) in our answer



We know that sinx/ cosx = tan(x)
Also 1/ sin(x)= csc(x)
so it becomes 2csc^2(x) tan(x) , Right hand side
Hence verified
Answer:
a(-1)^(n-1).
Step-by-step explanation:
This is a Geometric Sequence with common ratio r = -1.
The general term is a(-1)^(n-1).