please answer for the questions in attatchement
and get yourself marked as brainliest
no irrelavent answers please..
from 16 to 30.
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Answer:please mark me as brainliest
Step-by-step explanation:
16)Answer:
Solution :-
Here, we have
9x² - 9(a + b)x + (2a² + 5ab + 2b²) = 0
Therefore,
Constant term = 2a² + 5ab + 2b²
= 2a² + 4ab + ab + 2b²
= 2a(a + 2b) + b(a + 2b)
= (a + 2b) (2a + b)
Coefficient of middle term = - 9(a + b) = - 3[(2a + b) + (a + 2b)
Then,
⇒ 9x² - 9(a + b)x + (2a² + 5ab + 2b²) = 0
⇒ 9x² - 3[(2a + b) + (a + 2b)]x + (2a + b) (a + 2b) = 0
⇒ 9x² - 3(2a + b)x - 3(a + 2b)x + (2a + b) (a + 2b) = 0
⇒ 3x[3x - (2a + b) - (a + 2b) [3x - (2a + b)] = 0
⇒ [3x - (2a + b)] [3x - (a + 2b) = 0
⇒ [3x - (2a +b)] = 0 or [3x - (a + 2b) = 0
⇒ x = 2a + b/3, a + 2b/3
Hence, x = 2a + b/3, a + 2b
17) in attachment
18) sorry i am not able to find
19)in attachment
16) ii)a²b²x² - (4b⁴ - 3a⁴)x - 12a²b² = 0
Here A=a²b²
B= -(4b⁴ - 3a⁴)
C= - 12a²b²
D=discriminant =B²-4AC=
=[( -(4b⁴ - 3a⁴)² - 4 x [a²b²] x - 12a²b²]
=[16b⁸ + 9a⁸ -24a⁴b⁴]+ 48 a⁴ b⁴
=16b⁸ + 9a⁸+24 a⁴ b⁴
=(4b⁴)² +2x 4b x 3a ² + (3a²)²
=(4b⁴+3a⁴)² [∵ (a+b)²=a²+b²+2ab]
Now, let us use quadratic formula
X = {-B ± √(B²-4AC)}/2A
= -( -(4b⁴ - 3a⁴) ±√ (4b⁴+3a⁴)² /2a²b²
={(4b⁴ - 3a⁴) ± (4b⁴+3a⁴)} /2a²b²
now taking positive sign,
=[(4b⁴ - 3a⁴) + 4b⁴ +3a⁴]/2a²b²
=8b⁴/2a²b²
x=4b²/a²
taking negative value :
=[(4b⁴ - 3a⁴) - 4b⁴ -3a⁴]/2a²b²
=-6a⁴/2a²b²
= -3a²/b²
∴X=4b²/a² , -3a²/b^2
20)f you want to do it by trial and error, which is how I did it the answer is
(2x - 3)(3x + 5)= 0
Hence, x = 3/2, -5/3
A more systematic approach:
Multiply 6 and -15: 6*-15 = -90
Look for 2 integers that multiply to give -90 and add to give 1: 10, -9
Hence, 6x^2 + x - 15
= 6x^2 + 10x - 9x - 15
= 3x(2x + 5) - 3(2x + 5)
=(2x - 3)(3x + 5) = 0
Hence, x = 3/2, -5/3
21)The first term is, 12x2 its coefficient is 12 .
The middle term is, -x its coefficient is -1 .
The last term, "the constant", is -1
Step-1 : Multiply the coefficient of the first term by the constant 12 • -1 = -12
Step-2 : Find two factors of -12 whose sum equals the coefficient of the middle term, which is -1 .
-12 + 1 = -11
-6 + 2 = -4
-4 + 3 = -1 That's it
Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -4 and 3
12x2 - 4x + 3x - 1
Step-4 : Add up the first 2 terms, pulling out like factors :
4x • (3x-1)
Add up the last 2 terms, pulling out common factors :
1 • (3x-1)
Step-5 : Add up the four terms of step 4 :
(4x+1) • (3x-1)
Which is the desired factorization
22)in attachment
23)sorry i am not able to solve the question
24)4√3 x² +5x -2√3 =0
⇒4√3 x² +8x -3x -2√3=0
⇒4x(√3 x+2) -√3(√3x +2) =0
⇒(√3x +2)(4x -√3) =0
⇒(√3x +2) =0 or (4x-√3) =0
⇒x = -2/√3 or √3/4
25) in attachments
26)Let --> y = ( a / ( a + b ) ) ;
--> x² + [ y + 1/y ]x + 1 = 0
=> yx² + [ y² + 1 ] x + y = 0
=> yx² + y²x + x + y = 0
=> [ yx + 1 ][ x + y ] = 0
=> x = [ - 1 / y ] || x = - y
=> x = [ ( - a - b ) / a ] || x = [ -a / ( a + b )
27)4x²-4a²x+(a⁴-b⁴)=0
or, 4x²-2{(a²+b²)+(a²-b²)}x+(a²+b²)(a²-b²)=0
or, 4x²-2(a²+b²)x-2(a²-b²)x+(a²+b²)(a²-b²)=0
or, 2x{2x-(a²+b²)}-(a²-b²){2x-(a²+b²)}=0
or, {2x-(a²+b²)}{2x-(a²-b²)}=0
Either, 2x-(a²+b²)=0
or, 2x=a²+b²
or, x=(a²+b²)/2
Or, 2x-(a²-b²)=0
or, 2x=a²-b²
or, x=(a²-b²)/2
∴, x=(a²+b²)/2, (a²-b²)/2 Ans.
28)in attachment
29,30,23 ,18 sorry i am not able to answer
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