A1. 12 i.e option D
A2. 3n-7 i.e option A
A3. -6n+20 i.e option D
A4. -70 i.e option C
Step-by-step explanation:
aₙ = a₁ + (n - 1) × d
aₙ = the nᵗʰ term in the sequence
a₁ = the first term in the sequence
d = the common difference between terms
Using the above formula to solve the first part, we have :
For the second part, we have :
For the third part, we have :
For the fourth part, we have :
The answer is 2 two(2x2)=4
