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प्रश्न
Solve the following equation by using formula :
25x2 + 30x + 7 = 0
उत्तर
25x2 + 30x + 7 = 0
Here a = 25, b = 30, c = 7
D = b2 - 4ac
= (30)2 - 4 x 25 x 7
= 900 - 700
= 200
∵ x = `(-b ± sqrt("D"))/(2a)`
= `(-30 ± sqrt(200))/(2 xx 25)`
= `(-30 ±sqrt(100 xx 2))/(50)`
= `(-30 ± 10sqrt(2))/(50)`
= `(-3 ± sqrt(2))/(5)`
∴ `x_1 = (-3 + sqrt(2))/(5) and x_2 = (-3 - sqrt(2))/(5)`
Hence x = `(-3 + sqrt(2))/(5), (-3 - sqrt(2))/(5)`.
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