Question Find the 40th term of the arithmetic sequence with a = 150 and a common difference of d =-4. 1.-6 2.6 3.-2 4.2
Answer: 1. -6 Step-by-step explanation: a1 = 150 a2 = a1 – 4 = 150 – 4 = 146 a3 = a2 – 4 = a1 – 4 – 4 = 146 – 4 = 150 – 4 – 4 = 142 … => an = a1 – (n-1)×4 => a40 = a1 – 39×4 = 150 – 156 = -6 Reply
Answer:
1. -6
Step-by-step explanation:
a1 = 150
a2 = a1 – 4 = 150 – 4 = 146
a3 = a2 – 4 = a1 – 4 – 4 = 146 – 4 = 150 – 4 – 4 = 142
…
=>
an = a1 – (n-1)×4
=>
a40 = a1 – 39×4 = 150 – 156 = -6