Matrix Multiplication and Element-wise Operations

Problem Statement

Implement functions to perform both matrix multiplication and element-wise multiplication on tensors.

Background

PyTorch supports two types of multiplication that behave very differently:

• Matrix multiplication: follows linear algebra rules (dot products of rows and columns)
• Element-wise multiplication: multiplies corresponding elements directly

Understanding the difference is crucial for neural network operations.

Your Task

Write two functions:

• matrix_multiply(a, b) — returns the matrix product of two tensors
• elementwise_multiply(a, b) — returns the element-wise product of two tensors

Output Format

Each function should return a tensor.