Lipids are the base molecules our bodies use to make

Lipids are the base molecules our bodies use to make hormones

tₙ =  2n² - 3

Step-by-step explanation:

Standard form of a quadratic equation:

y = ax² + bx + c

Apply same for the quadratic sequence:

tₙ = an² + bn + c

Substitute n with 1, 2 and 3 to get the system:

-1 = a*1² + b*1 + c  ⇒ a + b + c = -15 = a*2² + b*2 + c  ⇒ 4a + 2b + c = 55 = a*3² + b*3 + c  ⇒ 9a + 3b + c = 15

Subtract the first equation from the second and subtract the second equation from the third to get:

3a + b = 65a + b = 10

Again subtract the equations to find a:

2a = 4a = 2

Then find b and c:

b = 3a - 6 = 6 - 6 = 0 c = -1 - a - b = -1 - 2 - 0 = -3

Substitute the coefficients back into the equation of the quadratic sequence:

tₙ = 2n² + 0n + (-3) = 2n² - 3