Answer:
7x²-2x-12, -6x² +11x-4, -12x⁵+14x³-2x²+10x , -10x⁷y²
Explanation:
Q1. (5x²-3x-2)-(-2x²-x+10)
=5x²-3x-2+2x²+x-10
=7x²-2x-12
Q2. ( -3x+4)(2x-1)
expand bracket
-3x(2x-1)+4(2x-1) ( a+b )( a+b )=a²+2ab+b²
-6x²+3x+8x-4
-6x² +11x-4
Q3. -2x(6x⁴-7x²+x-5)
-12x⁵+14x³-2x²+10x ∵ aⁿ x aˣ =aⁿ⁺ˣ
Q4. (12x⁴ ) (-5/6)x³y² = -10x⁷y²