Question

[2 2 2]
4. If A = [2 2 2]
[2 2 2]

then A^3 - 35 A =

1) A
2) 2A
3) 3A
4) 4A​

Answer 1

Answer:

(All the arguments are in degrees)

Let the expression to be evaluated be x.

Since sin10=2sin5cos5, you get:

22–√(sin5+2cos40cos5−4sin35sin5cos5)=22–√(sin5+2cos40cos5−2sin35sin10)

We can write:

2cos40cos5=cos45+cos35

2sin35sin10=cos25−cos45

Hence,

x=22–√(sin5+cos45+cos35+cos45−cos25)=22–√(2–√+sin5+cos35−cos25)

Since

cos35−cos25=−2sin30sin5=−sin5

The final answer is 4