Question

(ax+by)^2+(bx-ay)^2 simplify​

Answer 1

(ax+by)² + (bx-ay)²

=> (ax)² + (by)² + 2(ax)(by) + (bx)² + (ay)² - 2(bx)(ay)

=> a²x² + b²y² + 2abxy + b²x² + a²y² - 2abxy

=> a²x² + a²y² + b²x² + b²y²

=> a²(x² + y²) + b²(x² + y²)

=> (a²+b²)(x²+y²)