Answer:
see explanation
Step-by-step explanation:
Using sum to product identities
cos x - cos y = - 2sin(
)sin(
) = 2sin(
)sin(
)
cos x + cos y = 2cos(
)cos(
)
Note that
sin10° = sin(90 - 10)° = cos80°
Thus
← cancel 2 from numerator/ denominator
=
× 
= tan45° × tan35° { tan45° = 1 ]
= 1 × tan35°
= tan35° ← as required
Answer:
A
Step-by-step explanation:
5-2 = 1/52 = 1/25 = 0.04
Answer:
1
7 ✔️
15
21
Only 7 is a prime number in this question.
Answer: Arithmetic and 3
Step-by-step explanation:
12 - 9 = 3 9 - 6 = 3 The common difference is equal and is three and so it is an arithmetic sequence
12/9 = 4/3 9/6 = 3/2 The ratio is not equal so this is not a geometric sequence