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If x3+y3=468x^3 + y^3 = 468 and x+y=12x + y = 12, then value of x4+y4x^4 + y^4 will be

Solution

✅ Correct Option: 4

Given:

x3+y3=468x^{3}+y^{3}=468 and x+y=12x+y=12

Step 1: Find the product xyxy

Using the algebraic identity for the sum of cubes:

x3+y3=(x+y)3−3xy(x+y)x^{3}+y^{3}=(x+y)^{3}-3 x y(x+y)

Substituting the given values:

468=(12)3−3xy(12)468=(12)^{3}-3 xy(12)

468=1728−36xy468=1728-36 x y

36xy=1728−46836 x y=1728-468

36xy=126036 xy=1260

xy=35x y=35

Step 2: Find x2+y2x^{2}+y^{2}

Using the identity for (x+y)2(x+y)^{2} :

(x+y)2=x2+2xy+y2(x+y)^{2}=x^{2}+2 x y+y^{2}

122=x2+2(35)+y212^{2}=x^{2}+2(35)+y^{2}

144=x2+70+y2144=x^{2}+70+y^{2}

x2+y2=74x^{2}+y^{2}=74

Step 3: Find x4+y4x^{4}+y^{4}

Using the identity:

x4+y4=(x2+y2)2−2(xy)2x^{4}+y^{4}=\left(x^{2}+y^{2}\right)^{2}-2(x y)^{2}

Substituting the values:

x4+y4=(74)2−2(35)2x^{4}+y^{4}=(74)^{2}-2(35)^{2}

x4+y4=5476−2(1225)x^{4}+y^{4}=5476-2(1225)

x4+y4=5476−2450x^{4}+y^{4}=5476-2450

x4+y4=3026x^{4}+y^{4}=3026

Therefore, the value of x4+y4=3026x^{4}+y^{4}=3026 and the correct option is Option 4.

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