Solve the inequality 3x²-12x+16 > 3x+4.
- (a)Solve the inequality 3x²-12x+16 > 3x+4.[3]
- (b)(i)Write 3x²-12x+16 in the form a(x+b)² + c where a, b and c are integers.[3]
- (b)(ii)Hence, write down the equation of the tangent to the curve y = 3x² - 12x+16 at the minimum point of the curve.[1]
Mark scheme
Marking points from the official mark scheme (May/June 2023). The mark or mark type is shown in brackets.
- [B1] 3x²-15x+12 [*0] oe where * is any inequality sign or =
- [M1] Factorises or solves their 3-term quadratic FT their 3-term quadratic
- [A1] x < 1 or x > 4 mark final answer
- [3] 3(x-2)² + 4
- [B2] for 3(x-2)²
- [B1] for (x-2)² or a = 3, b = −2
- [B1] for a(x+b)² + 4 with numerical values of a and b or c = 4
- [B1] y = their 4 STRICT FT their 4 from part (i)
Write your answer and get it marked
On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.
Sign up free →