Question

plzzz ans the question to be brainlist

Answer 1

Heya User,

<4>--> 2x²y + 3xy² = 15
=> 18 [ 2x²y + 3xy² ] = 15*18
=> 3 [2x]²[3y] + 3[2x][3y]² = 270 --> (i)

Also, [2x]³ + [3y]³ = 730  ----> (ii)

Adding (i) and (ii) --> 
-----> [ 2x + 3y ]³ = 1000
=> [ 2x + 3y ] = 10 <--- Ans.

<5> --> [ 9x² + 25y² + 4² + 15xy + 12x - 20y ][ 3x - 5y - 4 ]
===== [(3x)²+(-5y)²+(-4)²-{(3x)(-5y)+(-4)(3x)+(-4)(-5y)}] [3x - 5y - 4] >>> (i)

This is of the form :->
--> [ x + y + z ][ x² + y² + z² - xy - yz - xz ] = x³ + y³ + z³ - 3xyz

--> (i) changes to :->
--->(3x)³ + (-5y)³ + (-4)³ - 3(3x)(-5y)(-4) = 27x³ - 125y³ - 64 - 180xy <-- ANS

--> There you go with the Answers...