Answer:
17
Step-by-step explanation:
an=a1+(n-1)d
a22=-25+21(2)
a22=17
Which of the following sequences are not geometric? (check all that apply) a. 2,10,50,250,1250 b. 1,4,9,16,25,36 c. -4,-2,-1,-0.
Romashka [77]
A is geometric because each number is multiplied by 5.
B is not geometric because it is an arithmetic sequence.
C is a geometric sequence because each number is divided by 2.
D is neither geometric not arithmetic because there is no common ratio and there is not a pattern being added or subtracted to each number.
So, your answer should be B and D.
Answer:
see explanation
Step-by-step explanation:
Using the sum/ difference → product formula
cos x - cos y = - 2sin(
)sin (
)
sin x - sin y = 2cos (
)sin (
)
Given
(cosA - cosB)² + (sinA - sinB )²
= [ - 2sin(
)sin(
) ]² + [ 2cos(
)sin(
) ]²
= 4sin² (
)sin² (
) + 4cos² (
)sin² (
)
= 4sin² (
)[ sin² (
) + cos² (
) ← sin²x + cos²x = 1
= 4sin² (
) × 1
= 4sin² (
) = right side ⇒ proven
Answer: x=6 x=5
Step-by-step explanation: