Question

If a^2+b^2=13 ab =6 find a-b and3(a+b)^2-2(a-b)^2

Answer 1

Answer:

73

Step-by-step explanation:

a² + b² = 13

Adding 2ab on th sides

=> a² + b² + 2ab = 13 + 2ab

=> ( a + b )² = 13 + 2( 6 )

=> ( a + b )² = 13 + 12

=> ( a + b )² = 25

Subtracting 4xy on both sides

=> ( a + b )² - 4xy = 25 - 4xy

=> ( a - b )² = 25 - 4( 6 )

=> ( a - b )² = 25 - 25

=> ( a - b )² = 1

3( a + b) ² - 2( a - b) ²

= 3( 25 ) - 2( 1 )

= 75 - 2

= 73

Answer 2

Answer:

a - b = plus or minus 1

3 (a+b)^2 - 2(a - b)^2=73

Step-by-step explanation:

(a - b)^2 = a^2 + b^2 - 2ab

(a-b)^2= 13 - 2 ×6

(a-b)^2= 1

(a-b)=plus or minus 1

3 (a+b)^2-2 (a-b)^2

3 (a^2+b^2+2ab) - 2 (a^2+b^2-2ab)

3 (13+12)- 2 (13-12)

3 (25)-2 (1)

75-2

73