Question

sketch proper fig x-y-2 l (x 3) = 5√6 . l (xcy) = 2 √6 I then find y3​

Answer 1

Answer:

Solution:

Short Trick∶

⇒ x + y = 3

⇒ Let x = 2 and y = 1, then

⇒ x3 – y3 = 23 – 1 = 8 – 1 = 7

Detailed Solution∶

Given, (x + y) = 3 and xy = 2

As we know,

⇒ (x + y)2 – (x – y)2 = 4xy

⇒ 32 – (x – y)2 = 4 × 2

⇒ (x – y)2 = 9 – 8 = 1

⇒ (x – y) = √1 = 1

As we know,

⇒ x3 – y3 = (x – y) (x2 + y2 + xy)

⇒ x3 – y3 = 1 × [(x + y)2 – xy]

⇒ x3 – y3 = 32 – 2 = 9 – 2 = 7

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Step-by-step explanation:

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