To estimate y(0.70) using the Taylor method of order 2, we will first find y(0.70) using the initial condition and the given differential equation.
Given differential equation: y'(t) = 3y - 2\cos(t) - 7
Initial condition: y(0.50) = 2
To use the Taylor method of order 2, we need to find y(0.70) using the following steps:
Step 1: Find y'(t) at t = 0.50
y'(0.50) = 3(2) - 2\cos(0.50) - 7
Step 2: Find y''(t) at t = 0.50
y''(t) = \frac{dy'}{dt}
y''(0.50) = 3y'(0.50) + 2\sin(0.50)
Step 3: Use Taylor method of order 2 to find y(0.70)
y(0.70) \approx y(0.50) + h y'(0.50) + \frac{h^2}{2} y''(0.50)
y(0.70) \approx 2 + 0.20 \times y'(0.50) + \frac{0.20^2}{2} \times y''(0.50)
Now, substitute the values of y'(0.50) and y''(0.50) into the equation to find the estimate of y(0.70.
\text{Answer: } y(0.70) \approx 1.468143997 \, \text{(option d)}