Question

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Answer 1

Refer attachment for better explanation

✠EXPLANATION:-

Used formulae :-

• (a+b)² = a² + 2ab + b²
• (a-b)² = a²-2ab + b²
• sin²A + cos²A = 1

Here take the first condition . And do the squaring on both sides Then we can get the x² value .Similarly do, the same for the second condition . Then we get the value of y² . So take what we need to prove Substitute the values then simplify it . Then the proved ! L.H.S = R.H.S

✠Know more Algebraic

formulae:-

✠(a+ b)² = a² + b² + 2ab

✠( a - b )² = a² + b² - 2ab

✠( a + b )² + ( a - b)² = 2a² + 2b²

✠( a + b )² - ( a - b)² = 4ab

✠( a + b + c )² = a² + b² + c² + 2ab + 2bc + 2ca

✠a² + b² = ( a + b)² - 2ab

✠(a+b)(a-b) = a²-b²

✠(a + b )³ = a³ + b³ + 3ab ( a + b)

✠( a - b)³ = a³ - b³ - 3ab ( a - b)

✠If a + b + c = 0 then a³ + b³ + c³ = 3abc