find out the polynomial whose zeroes are (3α + 1) and (3β + 1)
Answers
Answer:
Given : alpha and beta are the zeros of the polynomial x2-4x+3
To find : the quadratic polynomial whose zeroes are 1/(3α+β), 1/(3β+α)
Solution:
α & β are zeros of the polynomial x²-4x+3
=> α + β = -(-4)/1 = 4
α β = 3/1 = 3
quadratic polynomial whose zeroes are 1/(3α+β), 1/(3β+α)
Sum of Zeroes = 1/(3α+β) + 1/(3β+α)
= ( 3β+α + 3α+β) / (9αβ + αβ + 3α² + 3β²)
= ( 4α+4β)/( 3(α + β)² + 4αβ)
= (4 ( 4) )/ ( 3 (4)² + 4(3))
= 16 / 60
Product of roots = 1/(3α+β) * 1/(3β+α) = 1/ (9αβ + αβ + 3α² + 3β²)
= 1/60
x² - (16/60)x + 1/60 = 0
=> 60x² - 16x + 1 = 0
Step-by-step explanation:
★ Gɪᴠᴇɴ :
- α and β are the zeroes
- x²-x-2
☢ Tᴏ Fɪɴᴅ :
- polynomial whose zeroes of (3α+1) & (3β+1)
☯ Sᴏʟᴜᴛɪᴏɴ :
↠ x² - x - 2 = 0
↠ x² - (2 - 1)x - 2 = 0
↠ x² - 2x + x - 2 = 0
↠ x(x - 2) + 1(x - 2) = 0
↠ (x - 2) (x + 1)
⠀⠀◉ (2) and (-1) are the zeroes
⠀⠀◉ Hence, α = 2 ; β = (-1)
⚘ Nᴏᴡ, Fɪɴᴅɪɴɢ ᴛʜᴇ ᴠᴀʟᴜᴇ ᴏғ ɢɪᴠᴇɴ ᴢᴇʀᴏᴇs :
→ 3α + 1 = 3 × 2 + 1 (α = 2)
→ 3α + 1 = 6 + 1 = 7
❊ Nᴏᴡ, ᴛʜᴇ sᴇᴄᴏɴᴅ ᴢᴇʀᴏ :
↬ 3β + 1 = 3 × (-1) + 1 [β = (-1)]
↬ 3β = -3 + 1 = (-2)
⠀⠀◉ α = 7 ; β = (-2)
❥ Hᴇɴᴄᴇ, ᴛʜᴇ ʀᴇϙᴜɪʀᴇᴅ ᴘᴏʟʏɴᴏᴍɪᴀʟ :
↦ f(x) = k(x²-[7+(-2)]x+[(7 × (-2)])
↦ k(x² - (7 - 2)x - 14)
↦ k(x² - 5x - 14)
☛ f(x) = k(x² - 5x - 14)