a+b=9m এবং ab=18m2 হলে a-b=?

a+b=9m এবং ab=18m² হলে a-b=?

A 3m

B -3m

C ±3m

D 8m

Solution

Correct Answer: Option C

a+b=9m এবং ab=18m²

(a+b)² = 81m²

=> (a-b)²+ 4ab = 81m²

=>(a-b)² + 4.18m² =81m²

=> (a-b)² =9m²

=> a-b =±3m