Question

Grade 12mathematics(√98-√50)² ​

Answer 1

Answer:

8

Step-by-step explanation:

Two different approaches:

Method 1

Apply radical rule √(ab) = √a√b to simplify the radicals:

√98 = √(49 x 2) = √49√2 = 7√2

√50 = √(25 x 2) = √25√2 = 5√2

Therefore,  (√98 - √50)² = (7√2 - 5√2)²

                                         = (2√2)²

                                         = 4 x 2

                                         = 8

Method 2

Use the perfect square formula: (a - b)² = a² - 2ab + b²

where a = √98   and   b = √50

So            (√98 - √50)² = (√98)² - 2√98√50 + (√50)²

                                      = 98 - 2√98√50 + 50

                                      = 148 - 2√98√50

Apply radical rule √(ab) = √a√b to simplify radicals:

√98 = √(49 x 2) = √49√2 = 7√2

√50 = √(25 x 2) = √25√2 = 5√2

Therefore,     148 - 2√98√50 = 148 - (2 × 7√2 × 5√2)

                                                 = 148 - 140

                                                 = 8