Verify the formula for n = 1, 2, 3, and 4.Is it correct? $$6 + 12 + 18 \cdots + 6 n = \frac { 5 n ( n + 1 ) } { 2 }$$
A) no
B) yes

Question

Quizplus · Accepted Answer

Let's check the formula for n = 1, 2, 3, and 4.
For n = 1: 
LHS = 6(1) = 6 
RHS = 5(1)(1+1)/2 = 5 
LHS ≠ RHS

For n = 2: 
LHS = 6(1 + 2) = 18 
RHS = 5(2)(2+1)/2 = 15 
LHS ≠ RHS

For n = 3: 
LHS = 6(1 + 2 + 3) = 36 
RHS = 5(3)(3+1)/2 = 30 
LHS ≠ RHS

For n = 4: 
LHS = 6(1 + 2 + 3 + 4) = 60 
RHS = 5(4)(4+1)/2 = 50 
LHS ≠ RHS

Since the formula does not hold true for n = 1, 2, 3, and 4, we can conclude that it is not correct. Therefore, the answer is B) no.

Verify the Formula for N = 1, 2, 3, and 4.Is