Find the first, fourth and eighth terms for a(n)=-3*2^n-1 !

What does x = in this equation x+3+2x=x+5

The ratios 3: 9, 4: 12, 5: 15, and 6: 18 are a pattern of equivalent ratios in the ratio table. which is another ratio in this pattern?

Look at this pattern ; 1,4,9, number 10000 belongs in this pattern . what’s the place of this number?