solve the problems..
Answers
4. If a=2 , b= -2 , Find the value of :
1) a² + b² = (2)² + (-2)² = 4 + 4
➳ a² + b² = 8
2) a² + ab + b² = (2)² + (2)(-2) + (-2)² = 4-4+4
➳ a² + ab + b² = 4
3) a² - b² = (2)² - (-2)² = 4 - 4
➳ a² - b² = 0
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5.When a = 0 ,b= -1 , find the value of the given expressions:
1. 2a+2b = 2 (0) + 2 ( -1 ) = 0 -2
➳ 2a+2b = - 2
2.2a² +b² + 1 = 2(0)² + 2 (-1) +1 = 0 -2 +1
➳ 2a² +b² + 1 = - 1
3.2a²b + 2ab² + ab = 2 (0)²(-1) + 2 (0)(-1)² + 0 (-1)
➳ 2a²b + 2ab² + ab = 0
4. a² + ab +2 = (0) + (0)(-1)+ 2
➳ a² + ab +2 = 2
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5. Simplify the expressions and find the value if x is equal to 2 :
1. x+7+4(x-5) = x + 7 + 4x - 20
= 5x - 13
5x - 13 = 5 (2) - 13 = 10 - 13 = - 3
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2. 3 ( x + 2) + 5x -7
3x + 6 + 5x - 7
8x -1 = 8 (2) - 1 = 15
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3.6x+ 5 (x-2)
= 6x +5x - 10
11x - 10 = 11 (2) - 10 = 12
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4. 4 (2x- 1) +3x + 11
8x - 4 + 3x + 11
11x + 7
=11 (2) + 7 =29