Advertisements
Advertisements
प्रश्न
Find : a + b + c, if a2 + b2 + c2 = 83 and ab + bc + ca = 71.
Advertisements
उत्तर
(a + b + c)2 = a2 + b2 + c2 + 2ab + 2bc + 2ca
⇒ (a + b + c)2 = 83 + 2(ab + bc + ca)
⇒ (a + b+ c)2 = 83 + 2×71
⇒ (a + b + c)2 = 83 + 142
⇒ (a + b + c)2 = 225
⇒ a + b + c = `sqrt225`
⇒ a + b +c = ±15
APPEARS IN
संबंधित प्रश्न
If a2 + b2 = 29 and ab = 10, find : a + b
If a2 + b2 = 29 and ab = 10, find : a − b
If a + b + c = 10 and a2 + b2 + c2 = 38, find : ab + bc + ca
Find: a2 + b2 + c2, if a + b + c = 9 and ab + bc + ca = 24
If a – b = 3 and ab = 10, find : a3 – b3.
If `2"x"-1/(2"x")=4`, find : `4"x"^2+1/(4"x"^2)`
If `3"x"+1/(3"x")=3`, find : `9"x"^2+1/(9"x"^2)`
If a + b = 8 and ab = 15, find a3 + b3.
If 5x – 4y = 7 and xy = 8, find : 125x3 – 64y3.
The difference between the two numbers is 5 and their products are 14. Find the difference between their cubes.
