Chemegate

GATE 2026 Chemical Engineering, Q35 · Numerical Methods

The correct answer is 1.24 to 1.26.

Question

Using single step trapezoidal rule, the value of 00.5(1+\int ₀^{0}.5 (1 + 16x 20x2)− 20x²) dx is ______ (rounded off to two decimal places).

Official answer: 1.24 to 1.26

Why

GATE 2026 official key: 1.24 to 1.26. f(0)=1, f(0.5)=1+8−5=4. Single-interval trapezoidal rule: (0.5/2)(f(0)+f(0.5)) =0.25×5=1.25.= 0.25 \times 5 = 1.25.

Explanation cross-checked for consistency. Final answer matches the official IIT answer key.