If x = (√3-√2)/(√3+√2) and y = (√3+√2)/(√3-√2),
Find the value of x² + y² + xy.

Step-by-step explanation:

x = (√3-√2)/(√3+√2) and

y = (√3+√2)/(√3-√2)

Find the value of x²+y²+xy ?

Given that

x = (√3-√2)/(√3+√2)

The denominator = √3+√2

The Rationalising factor of √3+√2 is √3-√2

On Rationalising the denominator then

=>x=[(√3-√2)/(√3+√2)]×[(√3-√2)/(√3-√2)]

=> x = [(√3-√2)(√3-√2)]×[(√3+√2)(√3-√2)]

=> x = (√3-√2)²/[(√3+√2)(√3-√2)]

=> x = (√3-√2)²/[(√3)²-(√2)²]

Since (a+b)(a-b) = a²-b²

Where , a = √3 and b = √2

=> x = (√3-√2)²/(3-2)

=> x = (√3-√2)²/1

=> x = (√3-√2)²

=> x = (√3)²-2(√3)(√2)+(√2)²

Since , (a-b)² = a²-2ab+b²

Where , a = √3 and b = √2

=> x = 3-2√6+2

=> x = 5-2√6 (1)

On squaring both sides then

=> x² = (5-2√6)²

=> x² = 5²-2(5)(2√6)+(2√6)²

Since ,(a-b)² = a²-2ab+b²

Where , a = 5 and b = 2√6

=> x² = 25-20√6+24

=> x² = 49-20√6 (2)

and

y = (√3+√2)/(√3-√2)

The denominator = √3-√2

The Rationalising factor of √3-√2 is √3+√2

On Rationalising the denominator then

=>y=[(√3+√2)/(√3-√2)]×[(√3+√2)/(√3+√2)]

=>y=[(√3+√2)(√3+√2)]×[(√3-√2)(√3+√2)]

=> y = (√3+√2)²/[(√3-√2)(√3+√2)]

=> y = (√3+√2)²/[(√3)²-(√2)²]

Since (a+b)(a-b) = a²-b²

Where , a = √3 and b = √2

=> y = (√3+√2)²/(3-2)

=> y = (√3-√2)²/1

=> y = (√3+√2)²

=> y = (√3)²+2(√3)(√2)+(√2)²

Since , (a+b)² = a²+2ab+b²

Where , a = √3 and b = √2

=> y = 3+2√6+2

=> y = 5+2√6 (3)

On squaring both sides then

=> y² = (5+2√6)²

=> y² = 5²+2(5)(2√6)+(2√6)²

Since ,(a+b)² = a²+2ab+b²

Where , a = 5 and b = 2√6

=> y² = 25+20√6+24

=> y² = 49+20√6 (4)

On multiplying (1) and (3) then

xy = (5-2√6)(5+2√6)

=> xy = (5)²-(2√6)²

Since (a+b)(a-b) = a²-b²

Where , a = 5 and b = 2√6

=> xy = 25-24

=> xy = 1 (5)

Now,

On adding (2),(4) and (5)

=> x²+y²+xy

=> 49-20√6+49+20√6+1

=> (49+49+1)+(20√6-20√6)

=> 99+0

=> 99

Therefore, x²+y²+xy = 99

The value of x²+y²+xy for the given problem is 99

→ (a+b)² = a²+2ab+b²

→ (a-b)² = a²-2ab+b²

→ (a+b)(a-b) = a²-b²

→ The Rationalising factor of √a+√b is √a-√b

→ The Rationalising factor of √a-√b is √a+√b

second option

step-by-step explanation:

the measures of a triangle equal 180. use that to find x.

2x+3x+4x=180

9x=180

9x/9=180/9

x=20

now you know x, you know angle a is 40°, angle b is 60°, angle c is 80°.

because angle a is 40°, the first option doesn't work.

because angle b is 60°, the second option does work.

when you add angle a and b, you get 100°. complementary means it equals 90°, so the third option doesn't work.

when you add angle a and c, you get 120°, which is not 100.